Yes! The Coleman trailers are really nice. We had one for years and wore that baby out with over 700 days of camping. That said, the company is gone and so is the service. Parts will get harder to come by. That doesn't change the product but it does make the product less valuable.
Condition is everything. A seven year old trailer can be in mid-life or near death.
Select a price you would be happy with and place it on the table. "I know it is not what you were looking for but this is what it is worth to me. If you want to give your camper a good home for that amount, please call me."
Negotiate with your head not your heart.