Stuff like used C band dish values tend to follow whatever the market will bear, think Regan's supplied side economics.......lol
What's available, the public market value, how hungry you are for it, etc. That can vary from 'get it out of my yard' to someone trying to recoup as much as they can from the 3 grand investment they made 10-15 years ago.
I've paid cash for 3 dishes. One a BV solid, the other two were eldery/widowed that really needed the money. $25 for a 7'5' Unimesh, jack, feed, and pole and the rx if she could find what her (deceased) husband did with it. (She never found it.) The other was an 8.5' solid spun aluminum, (LNA feed) with a heavy duty jack and an old pre VCII rx and sat mover box. I gave 100 bucks for it, which is prolly close to the scrap value of the heavy assed thing, and the old timer didnt have to deal with taking it down to scrap it.
All the others were come get it, but that's here. If they arent that plentiful in your area then you may have to lay out some greenbacks. The 10' Uni is a well built dish, The two I have are old enough to have survived several 100 mph plus storms over the last 10-15 years or so, and they are in good shape. Except for the dish to ring brackets that rust out/off relatively easily in this area, they are in very good shape.
So the question becomes.......How hungry are you?