This extension also integrates with the Location Profiles extension allowing you to create a really nice SEO focused landing pages helping your visitors learn about the area you work in.
The purpose of this extension is to generate leads by limiting a users access to sales data for free. Basically by having a user register for the site they can gain access to all the listing data that you upload. This gives you the ability to send them emails.
Once Logged in the user gets full access to the sales data that you have loaded.
Example of what a logged in user gets access to