In Florence:
Hotel Aline
Via 27 Aprile, 14
Tel 055 485877
One Star, Doubles with shower €35.
Venice:
Go out the train station and take a left..several one stars that are €50-60.
There's also a hostel down that direction (Casa Gerotto) that I dont believe has a lockout, but I'm pretty sure there was a curfew.
This website
http://www.cross-pollinate.com has reasonable hotels in Rome, Venice, and Florence and is run by an american couple in Rome who also own a great hostel there called the Beehive. No lockout, no curfew.