Guides
- AI valuation vs official appraisal: what each is worth and for whatAn official appraisal (certified company, Orden ECO/805/2003) is used for a mortgage, inheritance or court. A commercial valuation with AI is used to set a selling or buying price and argue it. They do not replace each other.
- Bare ownership: how the value is calculated and what discount to applyThe value of bare ownership is the full ownership value minus the usufruct. The lifelong usufruct is estimated using the fiscal rule 89 − age of the usufructuary (minimum 10%, maximum 70%).
- Garage, storage room and terrace: how annexes are valued without double countingAn annex is valued once: it either enters as its own component (coefficient on the living sqm) or is already inside the comparable's price. Counting it in both places inflates the value.
- How to audit an automated valuation (AVM) before signing itAn automated valuation is audited by asking for three things: sources with dates, comparables used and discarded, and the formula for each number. If the system cannot show them, the number is not defensible.
- How to create a valuation report with comparables that the owner will acceptA comparables report convinces when it shows the samples used, the discarded ones and why, the applied adjustments and a value band with its calculation. Not when it just shows a number.
- How to know if an Idealista price is inflatedA portal price is an expectation, not a value. It is cross-checked against the closing price/sqm of the area (Registradores, municipal appraised value), the median of comparable listings and the time it has been published.
- How to monitor a property and its area: price drops, new listings, withdrawalsMonitoring an area means periodically checking comparable listings, detecting drops, new ones and withdrawn ones, and discarding duplicates and cropped samples before notifying the client.
- How to read a nota simple and detect charges before valuingThe nota simple shows ownership, description, charges (mortgages, embargoes, easements) and limitations. Any charge is an indication that should be verified with the Registry before setting a price.
- How to value a property for investment: rent, yield and maximum priceFor investing, value is calculated from rent: market rent of the area (SERPAVI/INE), expenses, target yield and from there the maximum price to pay. It is then compared to the market selling value.
- How to value an apartment from the catastral referenceThe catastral reference identifies the property and gives built area, use, year, floor and annexes. It does not give the market value: for that it must be cross-checked with comparables in the area and official price sources.
- What an AI real estate valuation must meet to be reliableFive conditions: official sources with dates, deterministic arithmetic, the AI does not write the value, auditable receipt and fail-closed behavior. And a professional who signs.
- Where to check the real price per sqm of a neighborhood (official sources)Official sources are the INE, the College of Registradores, the MIVAU appraised value and, in Madrid and Barcelona, the neighborhood data from the City Council and the Generalitat. Portals provide asking prices, not closing prices.