There are a few similar posts out here if you want to search, but most say at least 25-35% off. Do a quick google search for the same make and model to get a ballpark. For example, my MSRP on the 2013 Jayco 28BHBE was $31,999 so I thought I got a great deal at $24,000, which was 25% off. But, after I did some searches, $24,000 was the going rate at multiple dealers, so there might have been some manufacturer incentives. My great deal was not that great, so I probably should have talked them down some more. It's the end of the season, so I would expect the deals to be easier to come by now. Good luck!
2013 F150 4x4 Lariat Crew Cab Ecoboost
2013 Jayco Jayflight 28BHBE 28'