WE WON THE LOTTERY!, We are moving the US and buying an RV!

Welcome!

For your rig, I suggest something slightly larger than 20'. I have a Sprinter based class C that is 24' and I think you might like it. Take a look at the Winnebago View/Itasca Navion floor plans, some are more usable than others.

You haven't mentioned a towed car, but the Mini is ideal! I tow an 08 Clubman and it's dead easy. Just hook and go, don't even need to leave a key in the ignition.

Here's a picture taken last year, we were in line for the ferry across the Yukon River at Dawson City YT