Safest Way With F2F Is As Follows.
Tip 1: Use a legit looking char. (If Possable)
Tip 2: Always have a fake convo with them such as Gold Seller " Hey man, here is the cash i owe you ", Buyer: "Thanks man, lets jump on our mains and do some pvp now" (Or something along those lines)
Tip 3: Use private buyers always safer.
Tip 4: NEVER get people telling you saying "Do you have the money, i bought of you?" It puts both of ur chairs at risk. Apparently wow keeps logs up to 3 months old. Never mention anything against the rules. Same goes with your buyer.
If everyone follows those simple steps i belive you would see alot less bans.
Example: Wow sees 200k gold transfered = Flagged. First thing they will look at is the chat logg so make sure it all looks legit.
Taking photos of the transactions may also help defend ur cause if they say u sold gold. All you have to do is say fuck off i owed the cunt then show your evidence to prove your innocence.