Buying in Spain without inheriting someone else’s problem

The Spanish purchase process puts the buyer’s protection almost entirely in the hands of their own lawyer. The notary checks that the deed is formally correct; nobody in the chain is paid to check whether the extension was ever legalised, whether there are unpaid community charges, or whether the seller can actually sell.

That is the work here: the searches before the deposit, not the signature afterwards. It is also considerably cheaper than the alternative, which is discovering the problem once the money has moved.