Grand Design will not hold you hostage to your selling Dealer for repairs. They with pre-approval, will authorize mobile RV tech or independent RV repair facilities. I’ve got a 2015 Reflection (bought new in 2015) and a member of several Grand Design forums and many, many other owners get warranty service thru independents.
Buy your RV where you get the best price, do a very through PDI having the selling dealer fix whatever you find wrong before signing on the dotted line. Then if you need something fixed after that, call GD and they’ll fix you up.