Think of actions that a client makes on your site as a point system.
Default Grading Value
Point Value - System Event
5 points - Account Activation
5 points - Contact Us Request
2 points - Save a Search
2 points - Send Listing to a Friend
5 points - Get More Info - Mobile
5 points - Neighborhood Valuation Report Request
1 points - Listing View
5 points - Property Inquiry
5 points - Dream Home Request
5 points - Sign Up
5 points - Neighborhood Report Request
5 points - Schedule a Showing
Using this system, we can determine if a client is really looking, or they are just browsing. Dilution is by default 3% a day and its configurable by site.