I see posts where people could not be bothered to take a picture of the actual item they are offering.
Instead they copy and paste an image from Amazon or other online source.
It has happened to me a few times that I discovered that the condition of the item is not even close to how it is presented. Sometimes it is not even the same model or brand.
I consider this to be false advertising. I manage a few groups on Facebook and I strictly forbid the use of stock- and marketing photo's.
May be OfferUp should implement that restriction as well.