Are you wanting to sleep 4 adults? It will be difficult to find a Class B with that capacity. To get four bed will require giving up storage space.
You don't mention what type of bathroom you want. Wet or dry? Do you need a shower or can you get by with just a pullout toilet?
Is your budget %5000? Or did you leave out a zero? A $5000 motorhome will have a lot of miles on it and/or will be over 15 years old. And unless it is a diesel, it is unlikely that you will get the mileage you say you require.
BTW, the View and Rialta are Class Cs.