A. I bought a VERY cheap used guitar from eBay. I didn't check the intonation beforehand, but when I put some heavier strings on and tried to set it up, I can't stop the fretted note being sharper than the harmonic. And I've got the saddles flush against the back of the bridge. The frets don't appear to be worn at all. How might this be solved? Do I accept that cheap guitars have these issues and have scale lengths that are a bit vague? B. I fancy putting a new neck on it. If I want a chunkier neck, what do I ask for (on parts websites or eBay auctions)? Are there any issues with the sizing of the neck pocket (if that's what it's called)? Any chance that a better neck would help with issue A too?