DO NOT MESS WITH PAYPAL. You can as an innocent victim be thrown from PayPal for life. There is so much online to read about that. Be perfect with PayPal because it is such a convenient service.
But ask them to do a bank transfer to your email addy or send a bankers check, and once you’ve cashed it, they can pick up the furniture.
Also report them to PayPal as a possible scammer.
Those bankers check are mostly fake also, demand cash and get you a counterfeit pen to make sure they are real. I sell high dollar items quite often and serious buyers don’t mind paying cash, they understand.
“But ask them to do a bank transfer...”
That’s the easiest way to do it. I just gave them my account number and password and they could put the money in without a hitch. Oh - except I forgot, and had to text them my mom’s maiden name which came up for them on that password verification question. Silly me!