We had a fairly long discussion about this a week or two ago over on the GF thread (I think it was that one, might have been BC/YC or the CL one). According to more than one CM and the wording on the Disney website cabanas can be rented to anyone staying at any WDW resort. The new YC/BC ones, however, do not allow that and you have to be staying at the YC/BC to rent one of those. So apparently this is the only official way to be allowed to pool hop to the Poly, CR, and GF. I called the DSS myself and asked about it, and that’s what they read from their info and other people got the same info when they called. I don’t think it’s done often, but I guess since I didn’t know you could even do it until I called I could be wrong and it could be very popular