certainly it is worth $1500 to the right buyer in terms of hard value. The reason it might sell for less or more than that is the ability to market it and the fact that it takes a buyer willing to put a lot of time in it. What is critical is if you want to commit to the project. You should be able to find one with few or no dents about the same age for $8 to $10 thousand, I would think.
Here are some other numbers to play with while you think. We paid 11,500 for our 32' 5 years ago. Then another $4500 to bring it up to the level we wanted. At that time I could not work on it so it went to Jackson Center to get the bill up a little. Then a limb fell on it so I have a major dent in the roof. Got a little insurance money but not enough to fix it. So far we are living with the dent but ours really does not show much. It is still parked under the live oak tree with the limbs so I am sorta afraid to spend much to fix it and have it happen again.
I noticed it has vista windows in the front. Check the floor and the frame under the vista windows in the front. Check the frame and the tongue. On ours the vista windows leaked long enough (the trailer was parked for 18 years) to rust through the A frame which is what I had to replace.