Your best bet is to connect with a few realtors and interview each one. Write out questions about propertiesand your particular situation. Email or Skype works for interviews.
After you choose the realtor with whom you feel the best connection, you should then proceed. Your realtor can fix you up to receive information on all properties that fit within your parameters as soon as they come out and/or as soon as they close escrow.. By watching sale prices, you will become more familiar with our crazy market.
Your realtor can give you links to sites that discuss the various districts/neighborhoods. And she can give you the names and contact information for mortgage brokers and bankers. Unless you are paying cash, you need to be pre-approved for your loan before making an offer.
Will you be coming out to look at properties and then make an offer. Or are you planning to buy site unseen. If this is your first purchase in San Francisco I would counsel you to make sure you see the property first. Also please go to http://www.sfgov.org,
the Mayor's official website, and check out rental rules. There are many rules about renting! Some can be circumvented by buying new construction.
I have been in the business for 24 years. Feel free to ask me questions. Check out my website for Resources & Links (Mortgage brokers/bankers), guides to neighborhoods and easy access to our MLS. I also have a weekly Newsletter which I am happy to send you.