Simple process to follow when you transact a business.
01. Domain name on sale, post the registration date, registrar ex. enom, godaddy, etc. If you have traffic information, that is a value sale.
02. Interested buyer agree to pay either paypal, credit card or using escrow. If you transact above $1000, it is safe to use third party escrow service. Personally I transact deals above $1000 using paypal if I know the other party. Simple business ethics.
03. If you receive the payment, you can simply push this to their existing account or create one for them.
Hope this help, best of luck to your sale.
TheWatcher