We use the cordless Dyson at home and in the trailer. It will carry enough charge to use it a couple times (probably more, but haven't been out long enough to use it more than twice LOL!)
I had thought about installing on-board vacuum, but when we bought the Dyson for home, those plans went by the wayside. Now if we're going to be out for more than 2 nights, we just toss the Dyson in the top bunk. If the top bunk ever needs to be occupied, we can just take off the hose and toss it under our bed.
Probably the best vacuum I've ever owned, corded or not, and it's A LOT better than our corded Dyson (1st gen, over 10 years old).
2014 Jay Flight 28 BHBE
2015 RAM 2500 6.4L HEMI, Tradesman 4x4, 3.73
Blue Ox SwayPro (BXW 1503)
Upgraded from an REI internal frame backpack and a Eureka 1/2 dome tent!