This is the English way of saying it - it is a Surveyor's building report, although in Italy the professional may not be a surveyor but an engineer etc.

I found this definition concerning the High-speed railway works that are being done in Turin where a protocol was signed in Florence for "testimoniali di stato" to be carried out.
TESTIMONIALE DI STATO:(in pratica una perizia tecnica che certifica lo stato di salute e la situazione dell'immobile