OK - so if I want to rent from someone how do I find out about how to buy their points, and how in the world do I even know what that will cost me? I looked but I coudlnt find a comprehensive resource on this - help!
If you looks at the rent/trade board under Disney Vacation Club Boards you'll find stickies at the top the first one is all about renting. The rest of the board is people looking to rent or looking for renters.
there is a link to the point charts for the DVC resorts in the top right-hand corner. figure how many pts you need from those charts, then find a renter (most likely it will cost $10-12 per pt).
here are some threads you can read to learn more about renting: