I was thinking of spending a long weekend in San Francisco in late Dec right after Christmas. I have never been with the wife and 3 year old. I was hoping to get suggestions on a good area to stay. Would like to keep do what people who live in San Fran do. I have done some of the more touristy things. Not planning on having a car but not out of the question if we need one for a day. I'm sure I can't go wrong in most neighborhoods but was looking for specifics why certain areas would be better for us to stay.
Yeah, no one needs a car in San Francisco, so good call on that! Public transportation is great, and if anything, just download the ridesharing apps like Uber, Lyft, or Sidecar (the most used in the city) and use those to get around. The latter probably makes the most sense with three people, including a toddler.
In terms of family friendly neighborhoods where the locals live, I would look at Airbnbs in Noe Valley (stroller central!), Hayes Valley, the Western Addition, Mission Dolores (specifically right by Dolores Park), and Nob Hill. All have are fairly lively, have their own flavor, and have decent public transportation. Since you're coming for a short time, though, you can never go wrong staying centrally located in the downtown Union Square, and the Fisherman's Wharf is touristy and a little out there, but could be a fun place for a three year old.
Hope you have fun! :)
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All the motels across from the Zoo, and next to the ocean are very good and somewhat cheaper than the rest of SF.