No disrespect to the band, but you would have to be pretty big to expect a premium on the going rate for your gear. Guitars could be an exception but you have intimated that this is gear that they had here in storage for touring so no 'special' pieces. Having said that, if when they came here they bought vintage jazzmaster's and gretsch's (gretschie?), they will have held their value. I have a good mate that works at vintage and rare guitars in Denmark street. He would give you a realistic value on the guitars, but you'd be better to sell it privately as you will get more despite the hassle. To be honest, it's pretty much the same as selling bike stuff!
Never, ever underestimate the stupidity of obsessive fans with disposable cash (and that goes for pretty much ANY band!)
Never, ever underestimate the stupidity of obsessive fans with disposable cash (and that goes for pretty much ANY band!)