If you're not already a Twitter pro, it's not to late to start. Here's how:
Build your profile using the same headshot image and description you use for your joinreal bio.
Find and follow the most influential Twitter users in your town. Twitter lets you search locally. For instance, if you want to search the Atlanta area, you'd type near:atlanta within:25mi #realestate to see a stream of people tweeting about real estate within 25 miles of Atlanta.
Start by retweeting the most interesting tweets from local establishments, volunteer organizations and people. Be sure to add a comment to add context before hitting the retweet button.
Once you've got the hang of the audience, start posting your own content. Don't make it too sales-y.
Like all social networks, it takes a while to find your audience and your voice on Twitter.