Worst hotel I've ever stayed in
I just spent six nights at the Hotel Metropolis. I had booked on Priceline, non-refundable, or else I would have left as soon as I saw the room. This was the worst hotel experience I've ever had. I'm 44 years old. I've traveled a lot. I've been to San Francisco more than a dozen times. This was not only the worst hotel I've ever been at in S.F., but anywhere, ever. And yes, that includes the $50 roadside motels I stayed at with my parents back in the 70's. The room was simply horrible. It was shabby and small and dirty. The bathroom was tiny and the tub's surface lining was peeling off in huge chunks. there was mold on the tiles. The single-pane windows were drafty. The bathroom had no heater. It was freezing to take a shower and the hot water often ran out. The actual hotel room itself was freezing cold, too. The heater didn't keep the room comfortable. It was in the 50's outside at night, so it was typical for November. So I presume the rooms are always cold.
Even worse than the room was the safety factor and the noise. I could hear everything going on in the street below. As many other reviewers have said, there are many homeless people in front of the hotel. They stand and scream and yell. Sometimes for 30 minutes straight. On my first night, I personally witnessed a drug deal taking place. That was scary and beyond disturbing. The same drug dealers were there every night and the air was filled with the scent of weed. If you have children, don't even think about bringing them to this hotel. You'd be exposing them to the worst of the worst.
All of this was terrible, but the worst was when, after two nights, we complained to the front desk clerk. She clearly had heard similar complaints before. She immediately offered us a choice of two new rooms. Both were much nicer than our original room. Still noisy and still cold, but bigger and cleaner and higher up, so the noise factor was lessened. 
My coworker arrived two days later. He was also given a terrible room. He complained, and they gave him a better room, too.
What kind of hotel does this? Gives their WORST rooms first, unless you complain? That's terrible customer service. And why are there so many horrible rooms? Why can't they upgrade every room? 
So, if you like dumpy, shabby hotels with bad customer service and poor security and safety, opt for the Hotel Metropolis. If you want something better, go anywhere else. Even a Motel 6. This place is horrific.