Google ranking is always related to a specific search term. The search term you are interested in as a real estate photographer is "real estate photography your-town". The idea is, when an agent in your-town does a google search for "real estate photographer your-town" you want to be listed as high as possible on the first result page so the see your web site listing and click on it.
Here is a quick and simple way to get your site high on the first page of search results exactly where you want it: Sign up for Google Places. Being registered on Google Places has a several of benefits:
A great example of this is I registered with google places in about 2008 when I did the first post on this subject and in my sleepy little town (Salem, Oregon) I got top ranking since I was the only real estate photographer registered on google places. So if any one googles "real estate photographer Salem Oregon" there I am king of the mountain. However, many folks in Seattle that read my post registered with google places so now, in Seattle if you register with google places you may not even get on the first page for the search term "real estate photographer Seattle".
Oh yea, I should mention. After registering your business with google places google will send you a letter with a pin number on it that they want you to use to verify your information. This is just to make sure your address is not bogus. If you don't go through the verification process eventually your business listing with google will go away.