you really can’t make that direct price comparison. For one, the retail booking is cancellable, the David’s rental is not. The retail booking also includes daily housekeeping, There is also some risk and loss of control with the rental booking. These things all have a price associated with them. (Especially the housekeeping has a real price, and the cancellability would be equal to an insurance cost.). Probably David’s could charge another few dollars per point, but not anywhere near what you calculated. As an owner (at WDW not GCH), If I can’t use the points for whatever reason, renting them out is a nice option to have.