You're ignoring the bigger issue: You will be holding $1000 in cash and a stranger will know this. I'd never, ever, ever do this. NEVER.

A couple potential negatives:

You Buy Jewelry and Person #1 shows up and takes it and runs. No one will pre-pay you because they'd fear you'd rob them. So you're carrying a $1,000 item around and someone know where you will be and when you will be there.

Or

You buy TV. You hand to Person #1, and receive $1000 USD. Yay...all is well. Person #1 leaves, and Person #2 (a friend of his/her) shows up and robs you. You have no recourse, and could even be hurt!

Just google "Craigslist robbery" Remember this story:
http://abcnews.go.com/US/florida-mar...3#.UEDp09ZlTFA