Some sellers accept PayPal, but you have to be careful. If any term that could be considered "gun" is used PayPal rejects it. They are one of the anti's. Not judging, I use them on eBay.
Some of the sellers, Gun shops mostly, will accept PistolPay. I have one of those accounts for buying on GunBroker and Guns America. I like the way PistolPay handles the transaction and provides some measure of assurance to the seller and the buyer.
Postal Money order is acceptable for almost all sellers.
If you are dealing with an individual, check with your LGS to be sure they will accept a firearm from an individual - some won't.
Good luck with the purchase.
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