I did as RWillis advised for paperwork and location with my seller but, rather than cash in hand, did a wire transfer so the possibility of being preemptively relieved of my cash by some unforeseen calamity was mute. It only added $15 to the transaction and can be accomplished in minutes if coordinated before hand. You might suggest the same to your buyer if he is worried about carrying that much.
"Good judgement comes from experience. Experience comes from bad judgment."
Sirs Gawain & Galahad
Air #48582, WBCCI #4584