Hi Jan,
Hotel Ala
www.hotelala.com 3 stars hotel
I stayed there some years ago but since then they have refurbished it and it gets very good reviews... Check them at
www.tripadvisor.com A short walk from St Marks square. It's now part of Best Western chain. I seem to recall it was next to Bauer Grunwald. Has a vaporetto stop by it ( I remember well; I took it on my way from the airport with all my luggage. No money then for a water taxi! )