Silver Plattes does not pay much at all and are very selective! In frustration /spite I donated to "Bella's Voice" (next to Goodwill in Lynnwood) they, in turn support animal rescue. If I am going to give something away it would b to Bella's!
Unless the records and covers are in pristine condition or near to it don't expect to get much. Even if the records are rare/collectible. That's true of most record stores - they are selective in what take since they expect to sell them. If you just want to unload a couple of boxes of stuff you don t play anymore you're better off taking them to Goodwill or other charities.
I've never actually sold anything to them but I imagine that they'll let you know if you go in there. Their selection is pretty high quality for used stuff so if the stuff you have is beat up there's a good chance they may not want it. It's always worth a shot though.
Unfortunately, the answer here is you are going to have to bring them into the store to be evaluated. Some of the LPs could be valuable but there is no way for the store employees to know that unless they can see them.
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