Anyone bought used rig with musty smells or dog odors?

It seems to me that the units that smell do so because the owners did not CLEAN the way you should. We full-time, and I clean the carpets, furniture etc just like if I were in the house. It's the same with a used car. If the interior of the car is filthy and stinks, then they probably didn't keep up on maintenance either. I'm thinking same thing for a stinky rv. I would pass. Owners who take care of their rigs usually take care both under the hood, exterior care and interior cleanliness.