Re: Seaching real estate agents websites
Point2 is a great starting point they are free and they will allow you to get your feet wet. I believe they may have a mort calculator built right in. Once you decide to go with a more expandable template or a custom go with something that is supported by php / mysql so that you can take advantage of all the open source toys out there - there are about a million open source mort calc's out there that you can customize to your needs, and you will find it will be much easier to find developers for php than windows or coldfusion.
Starting LEC 7 soon but it won't be called LEC 7 - LEC 2012 coming soon!