From what I've gathered by reading and watching people, here is sort of what I've found out:
Roadtrek 170 -- Easy use for a daily driver... all but parking garages.
RT 190 -- similar.
144" Sprinter van -- doable.
Longer Sprinter vans -- doable, but will take up more than one spot, so stick the back end over a curb if possible.
A very short "C" like a Phoenix Cruiser 2100? Doable in length, width can be an issue.
A short "C" like a 23-25 foot model? No clue. Some people say it is very difficult for day to day chores, others manage to do it.
Longer models -- can be quite difficult, especially in urban areas with no free parking, even in the back 40 of lots.
It really depends on where you are. For example, downtown Austin, a longer van can be too much. However, smaller places that always have room at strip malls even on a busy Saturday afternoon, a 30-footer that takes two parking spaces at the far end might be doable.
If I had my ideal setup, I'd go with a 24-25 foot "C" which by itself is good enough to park almost anywhere and can tow 7500-10,000 pounds (some "C" models I've seen can handle this.) From there, an enclosed cargo trailer and a Jeep Wrangler. Depending on where I am going, I can just take the MH, stuff the Jeep in the trailer and take both, or take one or the other, depending on the occasion.
