William's place is wonderful - he has done a nice job of renovation while maintaining the character of the original. Beds were quite comfortable, and William provides ample linens, and towels. The kitchen is fully equipped with a fridge with icemaker, dishwasher, with detergent, lots of glasses, plates, cutlery etc. The bathroom is huge by NYC standards and includes a large tub with shower, and a compact washer and dryer (with detergent!). Our group of 7 did 4 days worth of laundry in 2 loads - no problem. Air conditioners were provided at both ends of the apartment and worked great. This place is large - it's the entire floor of the building. William describes his place as "cozy" which is usually a code word for "small", but not in this case.
The neighborhood is quiet by NYC standards. There are two subway lines available each about 5 minutes walk. The express takes you into mid-town Manhattan in 15 minutes or so. The neighborhood has a huge number of food offerings of all types, and though dominated by small mom-and-pop stores also has a few national chains.
While I wouldn't say that William's place has any downsides, the single bathroom might be an issue for a very large group, and the stairs could be an issue for guests with difficulty climbing stairs, especially if renting the 3rd-floor apartment (we were in the 2nd-floor apartment).