We had four people stay at Costa's place. We couldn't complain about the location as it was a 5 minute walk from the 7 train. Also, Costa was a great communicator and was quick to respond to all of my messages.
However, we do recommend that for longer stays and more than two people, you may have to purchase some of your own toiletries and it would be best to bring an additional pillow if you're used to more than one.