Foot for foot, not much difference at all between an A and a C.
A 25' A will have a different turning radius than a 25' C because of the wheel base, but neither of them are going to turn on a quarter much less a dime. You'll end up going around the block rather than trying to turn it around...
The only other thing is where your 4 corners are...in a C the front end is way out front of you because of the hood. In an A, you feel that you're sitting right up front looking straight down on the roadway.
A typical van is about 20' long so you're only 5' longer than a regular van...no it won't fit in a single parking spot but then with my hitch hauler on back, neither do I.
If you didn't find the C THAT scary to drive, then neither will the A except for the big front window and the wide open view.
That Class A that Gunny found looks to be a good deal - gas engine, pics show it to be in good shape, fairly low but not ridiculously low mileage.
Since the dealer got it as a trade-in, you should be able to wheel and deal on it down to the high 8's maybe 9 even.
For a 25'er that is nice - not only a full size bed but a sofa and chair as well....I think I could actually learn to like that.
And the mileage you're going to get on either of a 25' C or A is not going to be that much different...it won't be any where near close to what a van gets but you're hauling a full size home around!