I have a bass that I'm pretty sure has a broken truss rod. It never has tuned very well, the strings rattle when played, and if you tap the neck near the head you can hear a little rattle inside. So my question is, what's a typical truss rod replacement cost? Reason is, the only guitar repair shop I know of near me is way overpriced on everything, so I don't want to get ripped off here. For instance, I bought a bass for my girlfriend a few months ago for about $200, then saw the exact same one at this shop for $400... Also, are there any luthiers here that would be willing to look at it? How much would it cost to fix if I took care of all the shipping? Thanks, and its a Washburn AB-20 acoustic bass if that makes a difference.