The location of this place is superb! I can't imagine being closer to the city center. Nikita is great host who will give you great hints and tips for the places to be seen, things to be done, even provide you with some discounts at the places he has some connections with. The price is a bit higher, but you are right at San Marco square, so there is no expectation to be low. I recommend to keep your windows closed during night as the water is dripping through the canals which might make you want to go to the bathroom quite often. Also the tower bells are quite merciless to your sleep, but you are in the center of Venice, so it comes naturally.