The best parts are neighborhoods that have commercial districts with restaurants and other services, and good public transportation. Since you are now required by the city to live on your Airbnb site for 265 days per year, you cannot operate 2 seperate locations in San Francisco. If you are looking for a larger apartment and are planning on moving, your landlord will have to give you written permission to do Airbnb before the city will renew your license or allow you to transfer it to a new location.
This is a lot to ask a landlord, since his insurance will not kick in if there is major damage, because you will have turned his full time rental into a short term rental, they each require different insurance (I rent my own home and it took months to find additional insurance to cover a short term rental). So even with a willing landlord, you will have the added expense of paying for short term rental insurance (about $500 per year). The landlord would also have to deal with complaints of other tenants concerning strangers with access to the building. If another tenant moves out, because of your activity, the landlord loses income. In rent controlled apartments you are not allowed to earn more than the amount of your rent. This gets very complicated unless you own the building. The landlord is not allowed by law to rent short term unless he lives in the building and he is renting out his own unit, but none of the others for short term purposes. These restrictive rules are the city's intentional way of keeping enough apartment stock for residents like you to have a permanant home here.
You might get more information by googling San Francisco Short Term Rental Laws.
