If you're looking to host a large group, David's place is it. I was able to host my birthday here with without any trouble:
Cleanliness: The place was beautiful and clean on the inside, and there were even argon oil shampoo and conditioner for personal hygiene in each shower. There are towels for a large amount of guests to use, so you don't have to bring your own, and all the beds were made with hotel-style comforter and pillows and felt very clean. The décor felt homey and modern.
Space: If you're looking at a 22-person airbnb, odds are you want space for a large group. There are AMPLE amount of beds, bathrooms, rooms, and space to accommodate the amount of guests advertised. Each bed is queen size, even the ones in the room of bunk beds.
Access: The smartlock system on each of the doors is a God send for people who want to split off from the group. No keys needed. Also Boston is a quick Uber away.
Finally, David is courteous and swift in answering. 10/10 experience