retrorevival

Actually, I can't help with your value question. I'm not any kind of expert on used trailer pricing.

As for the fact that you've gotten no responses so far to your post, you'll just have to give it time. There are hundreds of new posts every day on the AirForums, and not everyone reads every one of them. But in a day or two I'm sure someone will have an answer for you— or else they'll at least have more questions to ask you before that can give you a meaningful answer. Either way, they'll get a dialogue started.

As for not having a VIN, if the present owner still has a license plate on it, then the DMV will know the VIN. Just need to go to the DMV to get a duplicate registration if the original is lost, and the VIN will be right there on the form. If it was ever insured and the owner still has an insurance card for it (even if the insurance is expired) then the insurance card will have the VIN as well.