As Cruis-o-matic alluded to, there is technically no such animal as renting points.
DVC members can transfer points from one account to another -- theirs or someone elses.
When a non-DVC member uses points, what you are
really doing is having a member make a reservation for you, and then rent you that
reservation. So you have to go through the member to get the reservation in the first place, and they would also have to make any adjustments if your plans change.
The best way to understand renting is to go to the DVC Rent/Trade Board and read both the FAQ and the sticky entitled "A Word to the Wise." Then come back here and ask any specific questions you might have.
For points requirements, click on the link to DVC
Points Charts at the top of this page, then find the resort you want and check the points for the dates you are interested in.
Points usually rent for $10-12 per point. The rate has been pretty standardized at $10 for a while, but will probably creep up because a) owners' dues just went up, and b) DVC points stays are now eligible for the popular dining plan for stays after April 1. The dining plan will create more demand for rental points and the price will go up a little.