All good advice above. If you walk into one that looks like you could actually live in it, then sit down and watch how people move around in it. More important, be an eavesdropper. Listen to what others like and dislike, especially if they appear to be experienced RVers who actually have lived in one. If you hear something you wonder about, ask what they mean or why it's good/bad. When a group of us who have been RVers a long time walk into a new motorhome we usually express our likes and dislikes! It may take the form of "I wonder what idiot thought that stupid little sink was a good idea for an RV" or "Where on earth would we put such-and-such" or "Why on earth do they think we would want four TVs when we're out camping and enjoying nature?" or "Oh I love that kitchen counter." You get the idea. Some of us aren't bashful about expressing our opinions so you might get an ear full! Of course, salespeople hate people like me, but we're the ones who have to live in it and we want what we want, not what someone sitting in an office in front of a computer thinks we should have. Envision how you would live in this space under varying conditions such as a week of rain with everything damp and the kids cranky because they can't play outside. Women will probably look at the inside differently while men will concentrate on what's outside but each should listen to the other because you have to agree together in the final analysis.
ArdraF