the biggest things to remember is that you are dealing with an individual and not with disney directly, you cannot call DVC directly if you have issues or want to make a request (they will only speak with the DVC owner), you likely will not have any sort of refund options if you need to cancel and that DVC rentals do not include daily housekeeping.
for more hand-holding, you can opt to rent through a broker like david (link below) who can explain things in more detail: