To add to Twidget's comment...
We periodically review the houses of dead, gone and/or inactive players. Some of those are still in use by others and often get transfered. Others get put back on the market and made generally available again.
Houses on West are in very high demand. If you're lucky enough to find one for sale, you can be sure it will not last long.
Lastly, and I say this every time: There is absolutely no reason why you cannot buy a house with someone else to make it more affordable. Haft Lake is expensive, yes, but if you split that 3 or 4 ways, it becomes much more affordable.