First, the location is absolutely amazing. Only a block off the main square of San Marco, this flat is a must if you are trying to see as much of the city as possible. The prices around here for restaurants and shops can be a bit high, but that comes with the area. Thankfully the island is small enough that you can walk to all of the other parts (with a map, because all of the streets and corridors can be confusing!).
Secondly, the flat was great. The room was very comfortable and big enough for two people. The shared bathroom with the host was a little small, but it had great water pressure and was very clean.
Third, the host, Nikita, was amazing. He was very friendly, spoke English very well, and was extremely helpful with recommendations and ideas on how to get around and where to go. He recommended a gelato shop that was amazing!
The only thing that I think other travelers should be aware of is that it is at the top of the building. It's not bad at all, it just didn't say anything about what floor it was on in the ad, though it did advertise no elevator.
As two American girls traveling before heading back home, we felt extremely safe the entire time we were there and were very thankful to find such an amazing place to stay on our trip to Venice! If we ever come back, we will definitely stay here again!