Custom modules/hacks for Real Estate Site

Project specification: Real Estate website running Joomla 1.0.12 and Hot Property 0. - ([login to view URL]) Enhance existing real estate website with more functionality and user-friendly features from third party modules, add-ons or hacks. Some of my ideas are listed below but your ideas and description of possible enhancement options are more than welcome. Example: [login to view URL] - I really like how this site looks. Offers a lot of rich search features. OBJECTIVES: A) Login or Signup to Our Web Site: Buyers - Save listings to “Favourite Listings”, show history of listings recently looked at, receive email or private message notification when a new listing matches your “Wish List”. Sellers – list & manage your property listings: upload photos, virtual tours/videos, add descriptions and contacts. View how many hits each of your listings have received since posted. (B) “For Sale By Owner” wherein each property listed will be a timed subscription with the fee based on various features and will be independent from other properties listed - can pay by PayPal or check. Once approved by the Administrator, seller can edit, manage, and can add pictures, delete pictures and all details. Note Bene: Is it possible to customize the Hot Property Agent Hack to assign different login buttons or signup options aimed at different types of users (or assigned Groups) i.e., "Buyer" and "Seller". Perhaps keep these login types separate to prevent the "Seller" from posting an active (live) listing without approval from the administrator. The seller can submit the listing for approval and select from available listing options such as “For Sale By Owner” which is subscription based. Example: [login to view URL] Thank you for your help.