For those concerned about the new dog policy at the YC, I recommend calling the phone number posted by @natebenma, which will connect you with a CM who can make special notations in your reservation about dog allergies, etc., as well as place room location requests.
I would suggest requesting "high floor, far away from dog area, and near main elevators/lobby."
I would suggest requesting "high floor, far away from dog area, and near main elevators/lobby."