I've done a fair amount of real estate writing over the past few years for both residential and commercial clients. For almost 2 1/2 years, I was the content manager for a local real estate agency. I wrote loads of real estate stuff for them. I've also written a good bit for freelance clients like BCZ Homes, Green Efficient, and Nest Home Solutions.
Here's an article I wrote last fall for Mindflash, a training company which lists tips for training real estate agents.