help me restore my grandads old Les Paul Guitar... Your Maya-brand, made in Japan Les Paul copy from the 1970's could be restored to look functional for a small amount of money. The tuning-machine could be purchased here: https://www.walmart.com/ip/Semiclosed-Acoustic-Guitar-String-Tuning-Pegs-Tuners-R6X9-Machine-P7I9-Sup-I8Q3/1942679920? Those and a set of new strings, and the guitar will look like a playable guitar. But to actually be a functioning musical instrument, will take more--probably more than the market value of the guitar, and probably more than a decent, recent vintage used guitar from this century. As others have said, the frets on this guitar a terribly worn, and replacing them could cost easily over $200. Non-functioning electronics is usually an easy fix for a tech, and the labor may cost more than the parts, but I'll just guess that the bench fee to trouble-shoot the electronics and parts might be another $100. ( a good deal of guitars with non-functioning guitars just have a broken connection at the output jack, which can be fixed by anyone with a soldering iron. the reason I gave a much higher estimate for repair is because even if that's all that's wrong with the guitar, most tech's would want to clean and /or replace some of the electronic components to insure that the guitar will continue to function in the future) And we don't have any idea from pics if there are any problems with the neck that might require even more work. This guitar was not at the top of the quality of Japanese Les Paul copies when it was made, and fifty-years of wear and tare haven't helped it. It's a guitar that I wouldn't pay $100 for, although some players do pay quite a bit more than than when they see the words "Made in Japan Les Paul copy". So figure-out what you want the guitar for: family heirloom or functioning musical instrument, and budget accordingly.
