Hi @Carl9,
As far as I know, there is nothing against doing this. I think by renting out your car though, you open yourself up to many issues especially liability. You could even put the payment through Airbnb if a person rents your car as a "request for money additional services". We had a guest who checked out this morning and we had a campfire last night and I she was commenting on our patio lights. I told her I had an extra box of lights that I was taking back to Costco and she said she would like to buy them from me. I put through on her Airbnb account and she accepted it.
Once again, as far as I know, you can do this but please read through the terms and conditions. I know leveral other people rent out bikes, strollers, boats and such.
David
Superhost Ambassador ~ Host Club Community Leader ~ Community Expert ~ Experienced Co-Host