My husband and I stayed in this apartment, and were joined by a couple of friends. It is amply big enough for four adults, although with more people, the one bathroom / loo probably would not suffice. It is immaculately clean with modern fittings and interior, yet set within a lovely old building. The most fabulous views and the proximity to all amenities - ferry, restaurants, lido etc, make this a fabulous holiday home for anyone not wanting to drive. It might not be suitable for older / less able bodied people as there are three flights of steps to get to the apartment, plus Varenna has plenty of steps too!
Luciana, the owner, was also extremely helpful when we had a small crisis during our holidays, which we were really grateful for.
We would definitely go back and would not hesitate to recommend to other groups like ours or families with older kids.