I think I snagged a MDD PS for $60 plus $15 shipping (LEM swap) a year ago for a local guy, they are more on ebay.
A IIgs I snagged last year worked for about 30 minutes and blew its PS, was cheaper to get a new one then bother fixing it ($5 plus shipping or something like that). I still have the dead one because I figured someday I might want to repair it to see what was involved.
As the 68K's get older you will find that the cost of parts will get high enough to justify repairs (superdrives anyone?). G4 machines are still in use so some people do repair/replace the blown PS in them, but I have seen dozens that blow the PS and are just parted out not deemed worth repairing.
A IIgs I snagged last year worked for about 30 minutes and blew its PS, was cheaper to get a new one then bother fixing it ($5 plus shipping or something like that). I still have the dead one because I figured someday I might want to repair it to see what was involved.
As the 68K's get older you will find that the cost of parts will get high enough to justify repairs (superdrives anyone?). G4 machines are still in use so some people do repair/replace the blown PS in them, but I have seen dozens that blow the PS and are just parted out not deemed worth repairing.