I would regard this as a yellow light, at least, on the transaction.
Packing a bike to ship (safely) is a PITA, especially if you have to go find a box, and it's not like you can mark up the shipping $50 to compensate yourself. There are plenty of ways to do a safe handoff: in a neutral location, with someone else present, etc. And the seller could (potentially) get paid in cash, thereby saving the PP fees. The reasons to NOT want an in-person handoff, by comparison, strike me as weak.
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I never think I have hit hard, unless it rebounds.
- Dr Samuel Johnson