Almost all of Benidorm's housing stock consists of high-rise apartments inside communities of owners. Before buying it is worth looking beyond the price at the community fees, the special levies (derramas) already approved or still unpaid and the state of the communal areas: in older blocks, a facade or lift levy can run into several thousand euros, which the buyer inherits if it is not checked in time.
The second feature of the town is the sheer number of foreign owners who do not live here. If you own an apartment and only spend part of the year in it, you must file the Modelo 210 every year: imputed income tax when the property is at your disposal, and rental income tax if you let it. This is the obligation most often overlooked, and the one that most frequently triggers letters from the Agencia Tributaria years later.
If you also rent to tourists, in the Valencian Community the property has to be entered in the Tourism Registry, and before that you need a certificate of urban compatibility from Benidorm town hall. Municipal procedures — habitation certificates, building licences, the padron — are handled at the town hall itself, while NIE and immigration files go through the National Police station in the town.