Chaznsc,
In my area, the saw that you're asking about would go for around $50 without the extension, and around $100 with the extension. If it's a Powermatic, then you're talking 10 times that.
I would suggest that you keep an eye for a pre-1980 Craftsman, or other quality brand, 10" belt driven, cast iron top, tilting arbor table saw. They have the same quality as a modern industrial level saw. Those can be had for $50 - $100. You may need to do a little work, but it's worth it.
Below is a before & after picture of mine. I paid $30 for it, put another $20 in materials. It's a waaaay too valued member of my garage family.