Well, I would recommend moving off Windows simply to save money if you need to scale to multiple servers. Server grade Windows costs quite a bit and the licensi

Well, I would recommend moving off Windows simply to save money if you need to scale to multiple servers. Server grade Windows costs quite a bit and the licensing is too complicated for me. Because of this I have made an effort to code in cross platform languages. However I would not start a rewrite of 100,000 lines of ASP (on the other hand 100,000 line is a LOT of code, perhaps it would be a lot less if written in something more powerful). I don't want to start another language war so I won't recommend any specific language, I just wanted to comment on the fact that you are limiting yourself to one OS and that might hurt. I like the idea, if executed and marketed well it could really help. Combine this with great real estate listing and search functionality and you might have a winning software.