You better also ask for information where such stay is legal and for obligations you need to fulfil.
Austria has rules that differ from Bavaria, and moreover that are different in the regions, e.g. Innsbruck can be different from Salzburg.
One issue is for sure that you need to see a doctor every two weeks.
And as far as I know prostitution is normally illegal in hotels (just like in Bavaria). One year ago the police in I think the greater Salzburg area was quite actively pursuing this in a hotel known for such activities.
Und für die Freier:
Maria ist ein Sweetheart...