The I/S Trunks ordered/replaced brand new incl. fender rails and rack runs just over $3,000.00.
I paid $800.00 several years ago [for my Tourer] and that was the average going rate for many years. I also think it's fair and would pay it again for a trunk system in good to great condition.
The ABS body parts are the main reason insurance companies total wrecked ones so fast. Especially on an I/S.
I would list for $800.00 + and wait for someone in need to repair their wrecked ride. It'll sell. Don't give it away!