For DRV's check out:
SOITCThey are one of several dealers that have good reputations. I bought our MS from Russ Dean Family RV in Pasco, WA as they were the closest dealer to me and they matched what other dealers would do. Going through the dealer you will be able to modify your unit quite a bit. Mix and match from various models, have special "stuff" you buy sent to DRV to be installed, and on and on.
This is our second MS and couldn't be happier. We snowbird in it and it is very livable, even with 2 German Shepherd Dogs as throw rugs! Lots of room. As with all rigs, there are a few minor issues and I will take care of what I want/can and let the dealer do the other. If we are ever in the market for another 5er, DRV would be at the top of the list.
Enjoy.