They have used everything. If it's not in the Boston store they most likely have what you need at another store in the US and can get it to you within 3-5 days or less. Super vintage and rare (and expensive) equipment is touch and go. I recently bought 4 used Roland AIRA devices in the last few months, and everything has been fantastic. TR-8, System-1, TB-3, and MX-1, each from different Guitar Center's all across the country.
Yes they do!
I believe they do sell keyboards on consignment like they do for guitars and amplifiers.
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