More like 15K of gear in this market :p
There’s no way to 100% de-risk anything. That said, I’ve sold a lot of audio components over the years (always at a loss), certainly into 6-figures, and no incidents of note. I’ve only ever sold through dedicated hifi audio marketplaces: e.g. here (audiogon), usam, head-fi. That’s a decent 1st filter. Next, you judge the potential buyer. All-green if their communication is good and feedback is 100%. I’ve sold to members with no feedback before, but I’m very wary of anyone with a NEW account and no feedback.
If they communicate poorly, request anything weird, or I just simply get annoyed by them - I STOP communicating. It’s really that easy. You get to be as picky as you like up front, BEFORE money changes hands.
I generally use PayPal, and don’t require friends & family. Probably your bigger risk here is damage or loss in transity, and there UPS and FedEx are pretty good in my experience. I’ve had UPS lose a VPI speed controller - that’s it. Either use factory packing or do a REALLY good job.