Too noisy
Hotel Frank looks lovely and the rooms are nice. However, there is no sound proofing at all and the noise from the street below, even from the 6th floor, was intolerable. Asked to switch rooms at 3am from outside room and desk was rude and said this is just how San Francisco is at night. No. I've stayed at many hotels in this area (Union Square) and never had this problem.
The concierges was very nice and helpful, however, and he gets 5 stars.