....and another thing :).....50 amp is not necessary unless you're in a big RV with two or more air conditioners and are unfortunate enough to stay in extremely hot temps.
If you have a smaller RV with only one air conditioner you'll be just fine.
Even though we had a 40' motorhome with two airs, we got by very well on 30A at times and boondocking lots of times. :)
When we full-timed in our 33' 5th wheel with one air and 30A we had no problems with staying cool.
Again, there is absolutely no 'correct' way of having the right RV for full-timing. It can be done in anything.