San Francisco in June for three months on a J1 visa. Tips Advice etc?

My son and two friends are going to San Francisco in June for three months on a J1 visa. Does anyone have experience of apartment living, tips etc for the three months and good locations. We are trawling the internet at the moment but would appreciate any help.

Lucky him! So jealous. It is a fantastic city to visit. General geography tips. The San Andreas fault lies to the south of the city. It passes close to Daly City. However, within the city itself south of Market Street (which is a good street to orient yourself by) is very flat and mostly on reclaimed land. It is a bit less stable in earthquakes. North of Market is the older parts of the city. Chinatown, Nob Hill, Tenderloin, Pacific Heights, North Beach, embarcadero, Russian Hill, etc. I'd probably stick north of Market myself. South of Market has its good areas and is generally cheaper than North of Market but it isn't as nice and it has some rough parts to it. Having said that, I would also avoid the Tenderloin area, aside from the name, it is not a good part of town. Around Union Square is a bit rough and not pleasant for living in. Focus on North Beach or Russian Hill I think. Pacific Heights will be too expensive and Nob Hill probably will be too expensive too. Bargain basement apartments will not be nice ones! If nothing there grabs your fancy try staying close to the Muni (http://www.sfmta.com) that way you will be close to an easy transport option. If you have to go further stick to the BART. Public transport is mostly easy and cheap (the cable cars are more expensive but it is one of the coolest commutes!).

Thank you so much. Very good information. I will pass it on to the boys. Hopefully they can get sorted with accommodation.