I shop at Midwest Buy and Sell a lot. Yeah, they messed up the name... they are not very tech savvy. They do test the gear before taking it in.
But they are the best kept secret in Chicago.
I don't need/want that preamp but this place is honestly my favorite guitar/amp shop I've ever been to (and if you ever are looking for an old Marshall or Les Paul at a reasonable deal, it's the first place I'd look).
FWIW I bought a 4010 from them earlier this year and mentioned that they had it priced so low. They flat out said yeah, the market is effing crazy right now, but we didn't really jump into the pandemic price gouge game.
All my $0.02, but these guys really are the salt of the earth types of folks a lot of people here on RT bitch about disappearing. Give them a call if you've got any questions about the gear. Wayne (the owner) isn't a guitarist but he tends to know what he's talking about, and he's always been honest with me about when he doesn't have an answer.
(I do not work for these guys, but they've taken care of me over the years and I want them to keep going for as long as possible, because they really are a dying breed)