wbwood wrote:
Don't smoke in it. Don't cook in it. Clean it often. Air it out often.
X2!
We aren't smokers so that's not a problem. Every RV we've been in that had bad odors was because of cooking. We had a tent and owned a pop-up for many years so were already in the habit of cooking outdoors. The only "cooking" we do inside is nuking stuff. We clean thoroughly before and after each trip, and open the windows whenever possible. We park it next to our house so opening windows and keeping it clean is fairly easy.
We had our last trailer for 10 years and had no bad odors in it. The dealer even made a comment to us on how clean it was.