Best place to move to in California

I think LA would be a better fit for you as there are more pros than cons for your needs. Warmer weather, almost year round tanning, fashion industry are all pros for LA. I would say the only thing San Fran would trump LA over is the public transportation, but as Lauren said they are improving that all the time. SF is a small city (geographically) compared to LA but if you situate yourself somewhere close to the beach in LA like Venice beach or Santa Monica, you would be very accessible to public transport which could get you to the garment district in downtown LA in about 30-40 minutes. Also the venice beach markets is a great place to test out your new fashion line. Roommate situations are abundant in both cities and either way you have to really screen the person well if you are moving in with someone you don't know. Cost of living may be a little less in LA as well.