I've purchased a number of basses sight unseen. All needed at least a basic setup. Two required somewhat more. One, a Nordstrand NJ6, was purchased on a whim being totally different from all my other sixes. It had a couple of minor electrical issues, a few cosmetic issues and in serious need of attention to the truss rod. It repaired fine and was moved on because I couldn't bond with it. The second needing a bit more work was an Alembic Elan+ four-string. It needed a pickup reset, a complete setup addressing bridge and nut issues caused by someone not knowing the pickup mount was broken (they raised both so the strings would clear the poorly-mounted pickup), and a minor crack in the fingerboard needed filling. (A little filing at the end of the fingerboard to create a little Ebony sawdust to mix with the filler set in the crack so the repair is now undetectable.) The Alembic was under-priced by a wide margin, so I figured it needed a little attention. My tech put it right for a minor fee and I've kept it to this day even though I'm really more of a six-string guy now. Like OP, all of those needing a setup played beautifully once they received a little attention, which begged the question; had the seller bothered to set it up would they have sold it?