I've purchased games at a distance.
The buyer usually takes care of all the shipping paper work and finding a provider. It's the buyers responsibility to get the coverage that he/she desires. Your job as the seller is to pack the pin to get ready for transit.

1. You (the seller) should send the buyer extremely detailed pictures of the game he/she is buying so that there are no surprises when the buyer gets the game and for insurance purpose in case the shipper damages the machine. I'm talking about inside the backbox, under the playfield, all the playfield details, in the back, under the machine...etc.... you get the idea.

2. Talk extensively about every issue the machine has...even the extremely minor ones. Be thorough.

3. If you can skype and have the machine in the video with you assures the buyer that the machine is in fact real. And a video teleconference lets both parties know who they are dealing with.

4. Payment, you can do it a few ways.
a. paypal as a friend (saves the 3% fee you get charged but doesn't offer the buyer assurance)
b. paypal regular but add the fees you are getting charge (reassurance on the buyers end)
c. Email money transfer
d. Cheque (wait 20 business days until it clears and there are no surprises)

5. Take pictures of the game leaving your house or premisses. Show it getting loaded on the truck.

that's pretty much it.

Better be safe than sorry. If the cheque bounces and the machine is gone.......you're left with both your balls in a tight squeeze.