If you're looking for a cool Brooklyn experience in the best part of Williamsburg, I recommend Raphael and Sydonie's basement apartment. I stayed at the apartment for a month.
PROS: The location can't be beat. It's between the JMZ and the L lines (which is nice when either line has limited service) and in the quieter area of South Williamsburg (but still within 10 blocks of everything that makes W-burg great). Check in is super easy because it's keyless, coded entry. The aesthetic is great if you're into a rustic, vintage and authentically Brooklyn look and feel. While you're right on the street level, this strip of Berry Street is fairly quiet at night. Communication was super easy and Sydonie/Raphael were kind and accommodating. The shower had good pressure and got nice and hot quickly. The kitchen had anything you'd need for cooking meals.
CONS: They are very up front about the noise by the neighbors, so this should be no surprise. I've always lived in old walk-ups in NYC and while the walking upstairs is quite audible, it didn't bother me. The issue I had was with the child(ren) running back and forth, jumping, screaming and banging on the floor. It was only bad in the early AM (may want to bring ear plugs to sleep in) and in the early evening. Some days the running and jumping was a bit excessive to the extent that it shook the light fixtures and rattled glass objects around the apartment. The sheets were a bit scratchy and could definitely be upgraded. There were a few wear/tear and cleanliness concerns I brought up that Raphael and Sydonie were appreciative of and said they would address. Even considering these minimal cons, I would have been more than happy to stay longer.