Yes they do. You would need to take your gun in to Coppell and talk to them there. I was thinking of doing a trade/sell, but had a friend who bought it instead. I did talk to grabagun.com and they said to bring it in and we could work out a price.
I don't believe they do, but if you go to their website, they have a good chat room where they will be able to give you the correct answer.
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