Rare items are shipped, then lost in the mail, only to be found for sale online. What's going on here? Here's what 7 On Your Side uncovered.

UPS requires its drivers to keep a log of items with values above $1,000, and customers can request a copy of this report. Gazeta requested a copy of the log, but has yet to receive it.

UPS requires its drivers to keep a log of items with values above $1,000, and customers can request a copy of this report. Gazeta requested a copy of the log, but has yet to receive it.

Indeed, the company’s terms and conditions show that if a customer doesn’t declare a package’s value, UPS’ maximum liability is $100 plus the cost of shipping the lost item.

In addition, UPS said only the shipper — Four Seasons Sports — could file a lost items complaint and request an investigation into the gun's whereabouts, Bailey said.

Now, two other viewers say UPS told them the one-of-a-kind items they were shipping were also lost, and the shipping containers discarded -- one of those items now possibly for sale on eBay.