Every InmoBuyer analysis transforms market data into useful signals: price positioning, comparable reference, reliability score and, depending on the plan, a negotiation margin signal.
InmoBuyer works with local references, comparable listings and, where available, registered transactions. The goal is not to produce a certain value, but a useful, contextualised signal accompanied by a reliability level.
The property is compared within its reference zone when data is sufficient. If the zone is too limited, the analysis displays an appropriate reliability level.
The asking price is adjusted according to available features: surface area, condition, terrace, pool, lift, parking, exterior, sea view and other relevant criteria.
Every analysis displays a reliability score. If data is insufficient, InmoBuyer flags it rather than producing artificial precision.
Market references are updated regularly. Calculations are re-run to avoid stale results.
The reliability score indicates whether the available data allows a solid, acceptable or cautious reading. It never transforms a data-poor zone into a certain estimate.
For certain rare criteria, InmoBuyer may widen the reading to a broader area to measure their prevalence. The reference price remains tied to the relevant price zone. The displayed reliability accounts for this widening.
Identify the property's reference zone from its location and available data.
Calculate a price reference from recent comparable listings, segmented by zone and property type.
Account for available criteria: surface area, condition, terrace, pool, lift, parking, exterior, sea view and other relevant factors.
Display a confidence level based on data quality, reference volume and local dispersion.
Confront listings with the notarial real-sales universe of the same area and the same typology, to calibrate the margin signal when this data is available.
Deliver an adjusted comparative price, a reliability score, attention points and, depending on the plan, an indicative negotiation margin.
Why our value references can sit below published prices.
In many areas, prices published on portals sit above the actual sale prices recorded before a notary. That difference — the market's 'fog' — varies by area. To measure it, InmoBuyer builds a real-sales universe from official notarial statistics by postal code (Consejo General del Notariado), keeping only the same typology as the listings being compared — second-hand flats against second-hand flats, never mixed property types. That universe is brought down to neighbourhood level through a postcode ↔ zone geographic bridge and statistically consolidated in line with the small area estimation methods used by official statistics institutes: each neighbourhood keeps its own signal when local data is solid, and is protected from noise when it is scarce.
When an area's over-listing excess goes beyond an accepted, documented threshold, we remove that excess from our value references (realistic value range, corrected median) — applied consistently to all value references at once. The listing's positioning against the published market does not change: what we correct is the VALUE reading, so you negotiate on a realistic basis rather than sellers' optimism.
Beyond the adjusted comparative price, InmoBuyer uses registered transaction prices to produce an indicative negotiation margin. This margin helps prepare the visit and a potential offer, without guaranteeing acceptance by the seller.
A contextualised indicator that crosses the asking price, the comparable listings reference and available registered transactions. It helps position a plausible discussion range.
It is not a valuation, nor a certified appraisal, nor a prediction of the price the seller will accept. It is not the actual sale price of this property.
Signal available depending on the active plan. Updated according to available registered transaction data.
The margin signal combines three data sources to estimate an indicative range, without guaranteeing seller acceptance.
The median price per m² of comparable listings in the reference zone forms the baseline, adjusted for property characteristics: surface area, condition and features.
Where available, notarial data — of the same typology as the analysed property — allows us to measure, neighbourhood by neighbourhood, the gap between listing prices and actual sale prices. This gap, statistically consolidated, constitutes the observed market margin.
Local tension (seller's or buyer's market) and publication duration guide the range. A property listed for over 90 days statistically offers greater negotiation margin.
Sources: notarial data (penotariado.com / ArcGIS), InmoBuyer BNG, Fotocasa/Idealista indices 2024-2026. Indicative value — consult a professional before any offer.
Visit observations are structured into 4 sections and converted into an indicative adjustment of the reference price, documented and capped according to recognised standards.
Each observation may or may not generate an adjustment according to defined scales.
A cap is applied to the total adjustment to remain within limits recognised by professional residential valuation practice. A legal alert (unlicensed terrace, electrical non-compliance) generates a specific warning without automatic adjustment.
The visit adjustment is indicative. It provides an objective, documented basis for preparing an offer or requesting additional expert assessment. It does not constitute a certified valuation.
Spain-applicable sources: IAAO Standard on Mass Appraisal §7.2 · Freddie Mac Selling Guide C1–C6 · Royal Decree ECO/805/2003 · REBT 2002 · Spanish residential markets 2024-2026.
Address search: CartoCiudad street referential © Instituto Geográfico Nacional (IGN) / CNIG, under a CC-BY 4.0 compatible licence.
After the visit and document verification, a synthesis combines all signals to produce an adjusted reference price and a prioritised list of key points of attention.
The initial price analysis (BNG), visit adjustment, legal alerts (unlicensed terrace, surface discrepancy between listing and land registry) and document data (ITE, EPC, community charges) are integrated into a synthetic summary.
The initial reference price is modulated by visit findings and document checks to produce an adjusted price. It is on this basis — not the listed price — that offer preparation is grounded.
Detected anomalies (structural issues, non-compliances, document discrepancies) are listed in priority order. Each alert comes with a recommended action: professional survey, clarification request, contractual condition or withdrawal.
This module is under development (Phase 3). The final synthesis will be available at the end of the visit journey.
InmoBuyer is a pre-offer decision tool. It does not replace professional expertise, a technical inspection, legal advice, or a bank appraisal.
The actual condition of the property, nuisances, charges, works, and legal situations must be verified by the buyer and qualified professionals.
InmoBuyer does not replace a certified appraisal or expert report required for mortgage financing. It provides pre-offer decision signals.
The margin signal is built from aggregated zone data. It does not reveal the exact price of an individual transaction nor the future sale price of the analysed property.
Pricing reliability decreases significantly for properties whose exceptional or highly specific nature multiplies the influencing factors beyond what can be automatically modelled. We advise against relying solely on the automated PPS score for the following types of properties: particular historical or architectural value, luxury level above the norm in ordinary or exceptional areas, castles, manor houses, religious buildings, windmills or boats converted into dwellings, and any property whose uniqueness makes peer comparison structurally impossible without the involvement of a sector professional.
InmoBuyer's methodological thresholds and controls are documented from recognised standards and references. The formulations below are kept simple and auditable.
Reference for dispersion and quality controls in residential mass appraisal.
Sector reference for confidence levels and forecast error reading in AVM models.
US regulatory reference on AVM reliability, quality controls, and model governance.
Professional reference on governance, sample sizes, and AVM model transparency.
Academic references used to frame geographic segmentation and avoid aggregating overly heterogeneous zones.