I've been on a business trip to Venice (for the Venice Film Festival) and stayed at the Caretoni.

The rooms are nicely decorated in the venetian style and are very comfortable, the breakfast is also very good but the special gem of this hotel is the service. The rooms are very clean and the cleaner (a shy oriental girl) is very efficient.

I've had problems in receiving an important fax and e-mail needed for the Festival and Elisa who is the Receptionist was extremely helpful, she did what she could to help me and finally, due to her assistance, all went well.
If you go to Venice, I strongly recommend the Antica Casa Carettoni.

We had been here from 20-22 Aug 2011.
Thumbs Down
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1. Mosquitoes - Too Many. The hotel staff care a damn to help by giving excuse of "Venice Problem". They do not even provide a repellant. Pathetic!!
2. Room Size - Too Too tiny (See my Pic). French Bed. we are thin and still could not fit in.
Even 2 suitcases cannot be kept.
3. AC/FAN - No Fan. AC Does not work. They ask us to keep windows closed to enable ac to switch on. But it never switched on. Summer nights were horrible. All 2 nights we could not sleep.
4. BREAKFAST - avoid.. looked like it was just a formality. No Choices. Breads were bad.
5. Staff - keep changing frequently. saw 5 receptionists at 5 diff times. Few were very rude/unhelpful/uncourteous. DEPRESSING
6 INTERNET - No wifi. They provide LAN cables and that too take 10Euro Deposit. What the heck!!!

Thumbs Up
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1. Proximity - Just next to rail station and to bus station
2. Location - On the main street of Lista Di Spagna - Always buzzing with activities

Avoid this. It was disastrous. It is better to stay in good hotels in Mestre..

Booked a "French double" room. It has to be said, the room was tiny. Open floor space was about the size of a double bed so it was difficult for 2 people to dress etc at the same time. The bed was 4 foot x 6 foot. The shower was, well imagine a normal shower cubicle and cut it in half diagonally. That said:

It was very clean and modern. Air conditioning worked well in the small space. Location was perfect. Dispite being on a main street, surrounded by cafes, restaurants, shops etc, we couldn't hear a sound from the street in our first floor room. The receptionist was extremely pleasant, making a point to greet us everytime as we passed through reception. This was a small hotel, i would think about 20 rooms so service seemed very personal and friendly. Breakfast was basic, and limited, but perfectly acceptable. Towels changed everyday and room cleaned. The only thing stopping me rating 5 stars was the size of the room, but i understand that there are bigger rooms available. Had we been made aware in advance, i would probably have paid a bit extra to stay in one of those.

Venice in general was a great place to visit. Doesn't have to be expensive, snackbars are plentiful offering Pizzas or plates of pasta for about 6 euros pp. paid 7.5 euros for a beer in a cafe, 3 euros for a can in an off-license, 1 euro in a supermarket, so is as cheap or expensive as you want it to be.

We stayed for 5 days which was enough to see most of the places of interest

Stayed at Antica Casa Carettoni for 2 nights in early July. I arrived in Venice by train and was very pleased to find my hotel located on Lista Di Spagna, a short walk from the station, lined with gorgeous cafe's, restaurants and gift shops.
The double room was spacious, clean, well decorated and affordable for such a great location. Everything you want to see is within walking distance including Ferrovia station for water taxis to San Marco square and Rialto Bridge. But I found myself drawn back to Lista Di Spagna for great dining and shopping.The only complaint I can think of was the continental breakfast.
Overall, would definately return for another stay!