I've rented spare points in the past and all the points for this UY because I don't plan to go back before 2017.
Be aware that there is a small chance of problems: if the renter trashes the room or cancels the credit card before checkout and leaves without paying, the owner might be considered responsible. There was a thread here on the Disboards of an owner whose account was blocked by DVC until the problem was fixed (I think it ended well). One post in many years, so not a very big risk, however it's there.
I've got 13$ per point, enough to cover MF for nearly three years to come.
You'll loose some money for Paypal commissions and then to change $ into £.
This year in Orlando I opened a Suntrust account, so I can receive money in $ and avoid some expenses. It may be worth considering if you think you'll rent DVC points often (it does not cost anything if you keep a minimum amount on the account).