Well if that is truly the case it will be unworkable.  In this little village alone I would say that 80% of the houses are over 50 years old and the majority are 3-4 storeys.  There just couldn't be enough inspectors to go around and most of the people I know probably couldn't afford the 900 euros.

I still suspect that it refers to flats or properties that are multifamilias.  The figures relating to the numer of properties involved certainly seem too few to include all town houses over 40 years old.