With no deck or motor I wouldn't pay more than $50. ,besides you can get a running mower for $350. or less.
I've seen a few advertised for free.
Yes the Rover ride on turned out good ,it was worth the effort for an enthusiast like yourself ,usually if I repair equipment for sale most people aren't interested if it's older than 10 years. I guess they can't understand how sound mechanically speaking these old ride on mowers are when refurbished, when they look at them they just think it' s old so must be no good.
Thanks for the Generator I got from you Norm ,I gave the main jet / emulsion tube a clean and it ran fine and the Governor was working.
