No answer fits, its one of those "pay what makes you happy" sort of things. Value? All you can count on is a WAG (wild-assed guess)
Its a novelty item that probably was working the last time it was used, I’m sure.
There’s not a lot to them. If it can hang on a transom and turns the propeller when you do whatever manual operation you’re supposed to do, then it’s a "runner". If nothing is broken or welded on it, and the actuating mechanism works, about the worst thing than can happen is they lose the grip on the handle.
I have seen them offered for sale in the 300-500 range and not get sold, if thats any help to ya.
Best,
PM T2