How about your travel expenses to pick it up? How much were your inflation loses over the period of ownership?A number of years ago, I got a great deal on a used Beretta Vertec Inox 92F. Mechanically fine, but the original owner wore it as his carry, but he had really nasty sweat and I had to have the frame refinished and cerakoted.
I rebuilt it as a 'ghost' Beretta (stainless parts). So I put maybe $120 of work into a $300 used gun and found a willing buyer at $750 - so I made some money on that one, but overall, nah. On the other hand, I wouldn't expect to make a profit on a new or near-new firearm I buy, use extensively, and then sell.