So in going through a relatives estate there 2 detectors they used, a Garret predator lll and a fisher aquanaut model 1280-x. They both work and have headphones.
Do they have any value? Or should we just toss them in the dumpster.

What I would do. I would look on Facebook and Craigslist, and see what they are selling for.

Silly, thinking to just toss, them, while detector's don't sell well on yard sells,, they do move, especially the name brand ones
which both of those are
and you know they work is even better, with headphones !

Difficult to give a price, however it's easy to solve with all the forums out now with the gold prices up

Even a couple hundred is better than throwing them away,, if you are bound to do that let me know I will pay the shipping to just send them to me !!

The fisher came out in 1985 and the other in 2004. I would give them to a grandchild or other relatives.