Welcome to iRV2 squonkone
After your last experience I think being a bit paranoid would be normal.
Although the idea of a kick back isn't out of the question I don't think it would be enough for an inspector to chance getting caught. You can always check out the inspectors reputation with the BBB. If you have
https://nextdoor.com/ it's free, you can post a question if anyone else locally has used this inspector and their opinion of the thoroughness and validity of the inspection.
Even with the paid inspection I'd print off a through inspection checklist from one of many online sites and still go over it myself. Maybe invite another RV owning friend to come with. Someone to keep the salesperson busy while you focus on the inspection.
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