The Fair Price Score (formerly the Reality Gap Score) is PropCheck's proprietary scoring system for measuring the divergence between a Portuguese property's registered legal state — what the Certidão Permanente (land registry), Caderneta Predial Urbana (tax record), and Licença de Utilização (occupation license) describe — and its likely actual physical condition. Scored on a scale of 0–10, it is the only systematic, document-based measure of this divergence available to buyers before purchase. A score of 0–3 indicates low divergence. A score of 4–6 indicates moderate divergence requiring further investigation. A score of 7–10 indicates significant divergence and should prompt a physical inspection before any contract is signed.

What the Certidão Permanente shows is the legal truth of a Portuguese property: who owns it, what encumbrances are attached, what area is registered. What exists inside the building is the physical truth: what was actually built, what was modified, what was added without a permit in 1994 and never registered anywhere.

In Portugal, these two truths frequently diverge. In some properties dramatically so. The causes are structural: decades of informal construction, incomplete registration processes, inheritance chains that passed properties between family members without formal documentation, and a municipal licensing system that recorded what was approved at construction but rarely updated when the building changed.

Since Simplex 2024 — DL 10/2024 (Decreto-Lei 10/2024) — the buyer who signs the Escritura Pública (notarised deed) inherits that gap completely and immediately. Every unpermitted work. Every unregistered modification. Every discrepancy between paper and reality. Yours, from the moment you sign.

The Reality Gap Score is PropCheck's system for measuring and quantifying that divergence before you commit — giving you a number, an interpretation, and a clear recommended action before the CPCV (Contrato Promessa Compra e Venda) is signed.

What Is the Reality Gap in Portuguese Real Estate?

The Reality Gap is the measurable divergence between what official Portuguese property records state about a property and what physically exists in that property. It is the distance between the Certidão Permanente's description of the legal state and the actual configuration, area, and condition of the building. Where that gap is large, it represents unregistered works, undisclosed modifications, or unlicensed changes that — under Simplex 2024 (DL 10/2024) — transfer to the buyer as legal liability at the Escritura Pública.

Every Portuguese property exists in two parallel realities.

The first is its legal reality — the picture held in official records across three non-integrated registries. The Certidão Permanente (land registry certificate), maintained by the IRN — Instituto dos Registos e Notariado — records ownership and encumbrances. The Caderneta Predial Urbana (property tax record), held by the AT — Autoridade Tributária e Aduaneira — records the property's fiscal description, assessed value, and area. The Licença de Utilização (occupation license), issued by the Câmara Municipal (municipal council), records the approved use and licensed physical configuration at the time of the last inspection.

The second is its physical reality — what someone standing inside the building would actually see. The floor plan that exists. The rooms that have been added. The terrace that was enclosed. The attic that was converted. The extension that was built over the garden.

The Reality Gap is the distance between these two realities.

In a property with no modifications since its original construction and licensing, the gap is zero or near-zero. In a property that has been progressively modified over four decades by multiple owners, each making informal changes without updating the registry, the gap can be substantial — representing tens of thousands of euros in Simplex 2024 legalisation liability.

The Plantas do Imóvel (architectural floor plans) archived at the Câmara Municipal and the Ficha Técnica de Habitação (technical housing file, required for post-2004 properties) provide additional dimensions of the legal picture. The Fair Price Score cross-references all available documentation to quantify how large the gap appears to be — and how certain that appearance is, given the documentation available.

→ Complete guide to property due diligence in Portugal

Why Does Registered State Frequently Diverge from Actual State in Portuguese Properties?

Registered state diverges from actual state in Portuguese properties because of three intersecting structural factors: a municipal licensing system that recorded initial approvals but rarely tracked post-construction changes; decades of informal construction culture in which modifications were made without engaging the licensing process; and inheritance chains that transferred properties between family members without triggering the formal registration updates that a commercial sale would require. These factors compound across time — an unregistered balcony enclosure from 1978 sits beneath a further unlicensed loft conversion from 2003, beneath a garden extension never submitted for approval in 2015.

Factor 1: The licensing system records approvals, not changes

The Licença de Utilização certifies a building at a specific point in time — typically at initial construction or a formally licensed renovation. It doesn't automatically update when the owner subsequently modifies the property. There's no legal mechanism that triggers a registry update when a homeowner encloses a terrace or adds a pool. The Câmara Municipal doesn't send inspectors when a balcony gets glazed over. The gap between the license and the physical reality accumulates silently, year by year.

Factor 2: Decades of informal construction culture

For much of the twentieth century — particularly through the 1960s, 1970s, and 1980s — informal construction was common across Portugal, particularly in urban areas experiencing rapid population growth and in rural areas without active enforcement. Families built what they needed. Modifications happened quickly, without architect engagement, without licensing, without registry updates. The result is a national property stock with a high proportion of buildings whose official description significantly understates their actual physical extent.

Factor 3: Inheritance without formal re-registration

When Portuguese properties passed through inheritance — as they frequently did, particularly in older families and rural areas — the formal registration process was often incomplete. The property was used, maintained, and sometimes further modified, but the legal records at the IRN and AT were never updated to reflect the new ownership or the changed physical state. Multiple-generation inheritance chains can produce properties where the Certidão Permanente describes a state from forty years ago, while the physical building has been progressively altered throughout.

Why this matters now more than it did before

Before Simplex 2024 (DL 10/2024), the Reality Gap was primarily a disclosure problem — sellers were expected to disclose known issues, and courts would sometimes apportion responsibility for undisclosed defects. The mechanisms were slow and uncertain, but they existed.

After DL 10/2024, the Reality Gap is a liability transfer mechanism. The buyer who signs the Escritura Pública accepts ownership of whatever exists in the physical reality, regardless of what the legal reality says. The gap becomes your liability, immediately and completely, at the moment of signing.

What Are the Five Most Common Reality Gap Triggers in Portugal?

The five most common Reality Gap triggers in Portuguese property — the modifications most frequently found to be unregistered and unlicensed — are: balcony and terrace enclosures, mezzanine installations, attic and loft conversions, pool and outbuilding additions, and kitchen or living area extensions. Each creates a specific document-detectable signature: a discrepancy between the registered area and the physical footprint, or between the licensed floor plan and the actual internal layout.

1. Balcony and terrace enclosures (varandas e terraços fechados)

The most common Reality Gap trigger in PropCheck's database. An open balcony — as approved in the original Licença de Utilização — has been enclosed with glass panels or aluminium frames, creating additional interior space. The result: the Caderneta Predial Urbana records the original floor area excluding the balcony, but the actual usable interior area includes it. The discrepancy is typically 4–15m² per enclosed balcony.

Typical legalisation cost if discovered: €5,000–€25,000 depending on size, municipal jurisdiction, and structural complexity.

2. Mezzanines and internal platforms (mezanines)

In high-ceilinged spaces — common in converted commercial units, older urban apartments, and loft-style properties — mezzanine platforms create additional floor area without being reflected in the licensed floor plan. The Caderneta records the original single-level area; the physical property has effectively 30–50% more usable space on the mezzanine level.

Typical legalisation cost if discovered: €8,000–€40,000 depending on structural intervention required.

3. Attic and loft conversions (conversão de sótão)

Converting non-habitable attic space into bedrooms, offices, or living areas is among the most significant Reality Gap triggers because the discrepancy in habitable area can be substantial — sometimes 20–40m² of additional living space that exists nowhere in the Licença de Utilização or Caderneta Predial.

Typical legalisation cost if discovered: €10,000–€60,000 depending on size and structural modifications.

4. Pool and outbuilding additions (piscinas e construções anexas)

A swimming pool added after initial construction — even one that's been there for fifteen years — requires a Licença de Construção (construction license) that may not exist. Similarly, outbuildings: garden studios, pool houses, storage structures, and garage extensions are frequently constructed without licensing. These additions appear on Google satellite imagery but not in any official document.

Typical legalisation cost if discovered: €5,000–€45,000 for pools; €3,000–€30,000 for outbuildings depending on size.

5. Kitchen and living area extensions (ampliações)

Structural extensions to the main living area — absorbing corridor space, merging a utility room, or extending into a terrace — create floor area that isn't reflected in either the Caderneta Predial or the Licença de Utilização. These can be subtle: a few square metres absorbed here, a partition wall removed there. The aggregate reality is a property meaningfully larger than its official description.

Typical legalisation cost if discovered: €12,000–€80,000+ depending on the extent of the extension and whether structural works are involved.

How Does PropCheck Calculate the Fair Price Score (0–10)?

PropCheck calculates the Fair Price Score through automated OCR (optical character recognition) analysis of uploaded property documents — the Certidão Permanente, Caderneta Predial Urbana, and Licença de Utilização — cross-referenced against each other and against available floor plan data. The algorithm identifies discrepancies in area, description, room count, and licensed configuration, weights them by severity and confidence, and outputs a score from 0–10. The score represents the probability and estimated magnitude of divergence between registered and actual state.

The calculation process works in three stages:

Stage 1: Document parsing

PropCheck's OCR engine reads each uploaded document and extracts structured data: registered area from the Caderneta Predial, licensed area and configuration from the Licença de Utilização, legal description from the Certidão Permanente, and any additional data from the Ficha Técnica de Habitação (for post-2004 properties) or Plantas do Imóvel (floor plans) where provided.

Stage 2: Cross-referential analysis

The extracted data is compared across all documents simultaneously. The algorithm looks for:

• Area discrepancies (Caderneta area vs. Licença area vs. declared purchase area)
• Description mismatches (room counts, floor counts, property type designations)
• Licensing gaps (Licença issued date vs. any modifications apparent in other documents)
• Regulatory flags (EPBD class, Simplex 2024 indicators, municipal enforcement records where available)

Stage 3: Score computation

Each discrepancy found is weighted by its severity (small area gap vs. major configuration mismatch), its confidence level (clear documentary evidence vs. inferential signal), and its Simplex 2024 exposure (whether the discrepancy represents a likely obra sem licença — unpermitted work). The weighted outputs produce the 0–10 score.

Score interpretation

What the score doesn't measure

The Fair Price Score is a document-based analysis. It identifies divergences in what official records say — it doesn't conduct a physical inspection of the building's structural condition, mechanical systems, or observable defects. A building can have a low Fair Price Score (documents consistent) while having physical defects invisible to documentary analysis. The score measures the legal-physical gap specifically.

What Is the Property Risk Score and How Is It Different from the Fair Price Score?

The Property Risk Score — formerly AIRCS, Asset Integrity and Regulatory Compliance Score — is PropCheck's composite score that integrates the Fair Price Score (legal-physical divergence), energy compliance status (EPBD exposure), and full regulatory compliance posture (Simplex 2024, municipal enforcement, licensing status) into a single 0–100 measure of a property's total integrity and compliance risk. The Fair Price Score is one dimension of the Property Risk Score. The AICF — Asset Integrity Correction Factor — then translates the Property Risk Score output into a market price adjustment.

Think of the three scores as a nested system:

Fair Price Score (0–10)

Measures one specific dimension — the divergence between a property's registered legal description and its likely actual physical state. It's the Simplex 2024 liability indicator. High score = significant risk of unpermitted works that transfer to the buyer at Escritura Pública.

AIRCS (0–100)

The composite score. It integrates:

• The Fair Price Score (physical-legal divergence dimension)
• The energy compliance dimension (current Certificado Energético class, EPBD deadline exposure, estimated retrofit CAPEX)
• The regulatory compliance dimension (Simplex 2024 flags, licensing completeness, active municipal enforcement)
• Market context (absorption time, comparable transaction data, VPT-to-price alignment)

A property can have a low Reality Gap Score (documents consistent — low Simplex 2024 risk) but a low AIRCS (because it's Class F with a large EPBD retrofit liability). The AIRCS gives you the full picture across all risk dimensions simultaneously.

AICF — Asset Integrity Correction Factor

The financial translation of the AIRCS. The AICF adjusts the property's declared market price to reflect the total compliance cost burden — the desconto castanho (brown discount) for energy class, the estimated Simplex 2024 legalisation liability where flagged, and the VPT reassessment risk. The AICF doesn't change the purchase price — it tells you what the price should be, given full information, and gives you the basis for negotiation.

Together, Reality Gap Score + AIRCS + AICF give a buyer three complementary answers:

• How much does the physical reality diverge from the paper reality? (Reality Gap Score)
• What is the total regulatory and integrity risk picture? (AIRCS)
• What should I actually pay, given everything PropCheck has found? (AICF-adjusted price)

→ Complete guide to property taxes, AICF, and true cost of ownership in Portugal

What Is "Transaction Truth vs. Asset Truth" in Portuguese Real Estate?

"Transaction truth" is what's documented in the legal records surrounding a property purchase — the declared price, the Certidão Permanente description, the licensed area. "Asset truth" is what the property actually is — its real physical extent, regulatory compliance status, energy performance, and condition. In an ideal market these would be the same. In Portugal's property market, they frequently diverge. PropCheck exists to bridge the gap between transaction truth and asset truth before you commit.

The distinction matters because most of the machinery of a property transaction is built around transaction truth. The IMT (Imposto Municipal sobre Transmissões — property transfer tax) is calculated on the transaction price or VPT. The Escritura Pública records the legal description. The mortgage valuation references the declared price. The seller's representations focus on the documents.

None of this machinery automatically captures asset truth.

Asset truth is what you're actually buying. The 110m² that you'll live in, versus the 94m² registered in the Caderneta. The unlicensed pool that makes the garden unusable in summer while you're waiting for legalisation. The Class F energy rating that means your utility bills are €300/month and you're facing a mandatory €28,000 renovation before 2033. The encumbrance on the Certidão Permanente that was meant to be discharged in 2019 and somehow wasn't.

Transaction truth closes the deal. Asset truth determines whether the deal was worth closing.

PropCheck's purpose is to make asset truth visible before transaction truth is locked in. The Fair Price Score quantifies the most common form of asset truth divergence — the physical-legal gap. The Property Risk Score integrates it with the energy and regulatory picture. The AICF translates it into a financial figure. The result is a buyer who negotiates with asset truth in hand, not transaction truth alone.

This framework — transaction truth vs. asset truth — is PropCheck's operating philosophy. It's why the platform exists. And it's the reason that the four mandatory documents (Certidão Permanente, Caderneta Predial, Licença de Utilização, Certificado Energético) are necessary but not sufficient: they represent the best available transaction truth, without addressing the asset truth gap that Simplex 2024 has now made financially decisive.

What Happens When PropCheck Gives a High Fair Price Score?

A Fair Price Score of 7–10 indicates significant document-level divergence — the kind of discrepancy that suggests probable unpermitted works exist and that Simplex 2024 (DL 10/2024) liability may be material. PropCheck's recommended protocol for a high score is: do not sign the CPCV until the source of the divergence is identified and quantified; request the Plantas do Imóvel from the Câmara Municipal; and commission a physical property inspection from a specialist inspection company before proceeding.

A high Fair Price Score is not a reason to abandon a purchase. It's a reason to investigate before committing — and a strong basis for price negotiation if the investigation confirms the divergence.

Here is the recommended step sequence when PropCheck returns a score of 7 or above:

Step 1: Do not sign the CPCV yet

The CPCV is legally binding. Once signed, your deposit is at risk and your negotiating leverage drops sharply. If the Fair Price Score is high, the information needed to sign safely isn't available yet.

Step 2: Request the Plantas do Imóvel

The Plantas do Imóvel (architectural floor plans) archived at the Câmara Municipal are the most direct way to compare the licensed layout against the actual property. Request certified copies. If the seller is reluctant to support this process, that reluctance is itself informative.

Step 3: Commission a physical inspection

A physical property inspection — where a certified inspector visits the property in person — is the definitive way to verify the divergence that PropCheck's document analysis has flagged. The inspector's job is to walk the property, measure the spaces, compare the physical reality to the licensed plans, and produce a report identifying specific discrepancies and their estimated remediation cost.

InspectOS is a specialist property inspection company in Portugal that carries out exactly this type of appointment-based physical inspection. InspectOS is entirely separate from PropCheck: it's an independent company operating an on-site inspection service with certified inspectors. PropCheck identifies the risk from documents; InspectOS confirms it from the building itself. The two services complement each other — PropCheck first, InspectOS where the score warrants it.

Step 4: Get a legalisation estimate

If the physical inspection confirms unpermitted works, commission a legalisation estimate from a licensed Portuguese architect before renegotiating. The estimate gives you a specific figure — not a range — to present in price negotiation.

Step 5: Renegotiate the price or rescind

Armed with the PropCheck Reality Gap Score, the physical inspection report, and the legalisation estimate, you have three options: require the seller to legalise before completion; negotiate a price reduction equal to the legalisation cost; or rescind the transaction (before the CPCV — at no cost; after the CPCV — requires the right contractual clauses).

→ Simplex 2024 Portugal: what every buyer must know about unpermitted works

Reality Gap Case Studies: Three Discoveries That Changed Purchase Decisions

Three anonymised PropCheck cases — one per common trigger type — illustrating how the Reality Gap Score surfaces divergences that buyer walkthroughs, agent descriptions, and standard legal checks routinely miss.

Frequently Asked Questions