The major WordPress theme vendors each have a real estate theme.  Enabling the theme is an inexpensive way to quickly launch a real estate website.  These themes either

a) have support for a third-party real estate IDX plugin

b) simply store the property listings as posts.  These properties have to be manually uploaded and updated

If you like variety and choice, BWG can seamlessly adapt to any of these real estate themes. – ElegantEstate – Estate (coming soon) – AgentPress (coming soon)