Try This Before Anything
This will not work for every piece, but musescore offers a tool that will automatically scan a PDF and try and turn it into a musescore file.
Go to musescore.com/import, make an account, and upload that PDF. It will attempt to make a conversion, and if it works it will save you a lot of work.
This won’t work far more often than it will, but it’s worth a try because it can save you hours of work.
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