Just a couple ways to lower your chances of a chargeback:
1. Simply don't use a payment method that can be chargedback. Companies like Western Union and Player Auctions offer this security but charge very high fees.
2. Sell to a highly trusted member (They usually pay very little keep in mind)
Here's also a small guide to paypal chargebacks that you might find helpful: http://www.sythe.org/market-discussion/1056701-paypal-chargebacks-limitations.html
Make them send you payment "gifted" they cannot chargeback that. Also if you do not, video or have a lot of screenies of the trade incase the person tries to chargeback. Paypal gives you chances to prove you are right
Your only real options are
1 - Receiving payment as a GIFT.
2 - Starting a donation link.

