A few years back we were in Disney and a tropical storm was moving in and we were able to cancel our flight with JetBlue and get a refund. We would of renting a minivan from
Alamo? (right at the car care center, near the Poly) and we drove home to NJ. We only paid a little over $100 for 3 days. It was a brand new van with television. We stopped at
Walmart, got a few CD's and saved hundreds of dollars because got refunded from the Poly for 2 nights also. (we had already been at WDW for 10 days so it was fine). Think it really depends on availability. We made the reservation the night before we needed the van.