It all depends on the terms of your rental contract.
This is the real key. A rental is a private transaction between the owner and the renter, and the terms are whatever the two agree on.
I don't rent my points, but from some of the threads I've seen, when there is a problem it is usually a problem of either vagueness or misunderstanding. Cancellation policies, in particular, should be crystal clear and very well understood by both parties.
To me, an owner who says, "Don't worry, I'll work with you if something comes up..." is really setting both parties up for difficulty. The truth is, there are so many variables in the owner's transaction that they may very well have zero options to "work with you" if a problem arises. Sometimes owners are too anxious (or desperate) to rent their points to really evaluate the full picture, and they paint themselves into corners.
The other thing that nobody thinks about at the time is whether the owner will really be
able to make a refund. What do you think the owner is going to do with your money...put it in the bank for safekeeping until you complete your vacation? Naw -- they're going to
spend it! That's why they often have to re-rent the reservation you paid in full in order to make a refund. We've seen several threads here (including one where renters did
NOT ever get their refunds) where the owner was unable to fulfill their promises when cancellations occurred.
My personal opinion is that both parties are best protected by a no-refunds policy. That obviously protects the owner, and the renter can get
trip insurance to cover their risks. If a renter thinks there is a possibility of a cancellation, they'd be much better off going through CRO and making a regular reservation.
Since trip insurance only covers non-refundable expenses, a clear-cut "no refunds" policy actually works to the renter's benefit as well. I've had to collect on trip insurance twice -- once on a ski trip and another time on a trip to Cancun. Both times, I was asked for a copy of the cancellation policies of the airlines, hotel, etc and was immediately reimbursed when I provided documents which said no refunds would be made. A contract that has workout provisions will probably lead the insurance company to evaluate the adequacy of the attempts to work things out, and that's not what you buy trip insurance for.