"The Chancellor Hotel has a great location on the Powell Street cable car line, half a block from Union Square and four blocks from Market Street. It's an old hotel, built 100 years ago, so the hallways are irregular and the elevator seems ancient. But everything works.
The hotel doesn't serve breakfast -- I recommend the croissants at One65 on O'Farrell Street, two blocks away -- but it does serve drinks at night. They also offer cookies, apples, a coffee machine and lemon-infused cold water in the lobby (although a couple of times they were out of the water). They also have a machine in the lobby to fill water bottles.
The hotel notes that they don't have air conditioning. That's generally not a problem. The rooms do have ceiling fans that help when it's warm.
I'd stay there again."