After his little Shpeel, I wouldnt trust him for a moment. "I dont take disrespect very well" would have been my first clue. Hes trying to intimidate you into submission, and it worked. Threatening to ruin your reputation for attempting to get help would be another sign. Sounds to me he has an ego problem and hes using it to get what he wants. Personally i would have handled it a little differently in the discussion. Direct accusation is not a very good way to proceed without proof. But since he admitted that it was working for a week in his posession then told you it never left his holster shows that hes nothing but a theif, willing to lie to get out of paying for the repairs.
You did the right thing in bringing this to the attention of the community. You could also have a community representative (someone well known and trusted in the community who is impartial) to mediate the issue. However you gave the gun back and refunded his money. While im not an expert on what constitutes a "completed trade" as that is more of a community opinion (since you are asking the community for help).
Post it on JOC... Roast the theif...
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