Donatella's appartement is spacious and luminous, and is very convenient to visit Venice. The railway and bus station of Mestre is just a few minutes away and of easy access, ans the bus (lign 2) takes you to Venice in less than 15min. This is really the better option if you want to go to Venice but have a smaller budget regarding the cost of hotels.
There is also a supermarket not far.
The bathroom and kitchen are nice, there is a small living room and then the bedroom, with lots of cupboards and space to put your stuff.
The only downside to the flat is its (lack of) noise isolation. The bedroom allows you to hear every word said within the neighboring restaurant, and the sound of its steel shutter at 00pm and 8am is atrocious. So bring some ear plugs.
And last information from my traveling experience there : I would definitely recommend the flat to a couple, but maybe not to a woman traveling alone... The neighborhood is not safe.
Other than that, the flat is really nice, comfortable, and definitely a good option to visit Venice! Very very convenient.