InspectOS · Before the viewing
They cost nothing, they need no documents from the seller, and they often decide whether the viewing is worth the drive.
about 20 minutes
Most mapping services keep dated aerial imagery and some expose a history slider. Step through the available years and watch the roofline and the plot.
What it finds: a pool, an annex or a roof extension that appears between two dated images, giving an approximate construction year. That year decides which regime applied to the work.
Street-level imagery is captured repeatedly on most Portuguese urban roads, and the capture dates are shown. Compare the façade across captures.
What it finds: a façade that gains a window, loses a garage door or changes render colour between captures. The capture dates bracket the works.
Agents describe what sells. Count rooms in the photographs and compare against the typology recorded on the Caderneta Predial Urbana.
What it finds: four bedrooms advertised where the tax record holds a three-bedroom typology. A photographed studio in what the records call a garage.
A specific question to arrive with. "Does the annex on the north side appear on the approved drawings, and what is the date of the last authorised alteration?" beats "is everything legal?", which invites a yes.