Vertimas - Italų-Anglų - l'indirizzo per l'invio dell'acconto è esatto,...

Here's the original English before I corrected it:
The adress for sending of the advanced payment is correct,
the apartment Biagio is located at the second floor*,
for acessing it there is a comfortable stairway,
it is for exclusive use of the apartment Biagio's guests.
In case of renunciation you must communicate me three months before.
--
*(British) first floor

ok thanks for your help, IanMegill!