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[omgwtfbbq]

I've only conducted one firearm PPT using the CGN marketplace and it was a FTF transaction so I can't really speak from a seller's perspective on that.

However, I've sold firearms parts and other, non-gun related items through the marketplace and I've shipped them to buyers without hesitation provided the buyer is willing to pay in advance via paypal gift or similar service.

[BigPimping]

I shipped a gun to a FFL once for a friend I knew who paid in advance. Besides that, I do not have time to pack it, insure it, send it.

[Bansh88]

It's a pain in the butt. BUT, if the price is up enough or the local purchase pool small enough, you will have to be willing to ship.
As this is generally just a statewide forum, its easier to assume a meet for sale.
Other forums that are country wide, shipping is commonplace.