We upgraded from Garden to Lagoon view on our Oct trip to the Poly. We were charged $50 (I think) per night for the upgrade. I think it is about $100 more per night when making ressie. I don't think we got a steal but the room was definitely worth the extra money to us. Sometimes people get complimentary upgrades but I don't know at which resorts. If you go at a busy time I wouldn't plan for an upgrade. We checked in on Columbus Day weekend and Poly was booked. We would've stayed in the garden view, but it was a really bad view and was a smoking room and we had specifically requested non-smoking.