What to buy

My wife and I were talking about what rig would be the best for us to buy. We are not going to live in our, but us it on trip and camping. Not wanting a large RV we are thinking of a 25ft or less class a or c. Why, many State or Fed. parks limit the size of the RV. Also our city will allow you to park a 25ft or less class a or c in you drive way like a car. All trailers have to be behind a fence in under 24 hrs. We do want a rig with a fixed bed. I have noticed that RV keep getting bigger as time goes. My question is what would be a rig I should looking for. Any recommendation what to and what not to buy. Thanks