any record (45/LP0) record collectors?

have a couple boxes of LP's to sell and a little over 600 45's. leaving out the rare versions, what is a general selling price for these? if you are at a show and a guy has boxes under the table, what are those going for? I think the neatest one I have is "Be Good to yourself at least once a day" with the fold out still intact. that may go up on the wall because it's so unique. and, yes, we have both kinds of music: country and western. and rock and/or roll and various others. Thanks!