When the firearm is sold private party-to-private party there is no requirement for a background check (At least last time I did it). However, if do sell a forearm to a private party make sure you draw up a very specific bill of sale. On all of my privates I have included that normal make/model/serial number stuff. I also included a statement along the lines of: "As of (DATE), I, SELLER'SNAME, am not liable for any acts related to the above listed firearm. BUYER'S NAME, intends to use this firearm only for lawful purposes." Or some such drivel. Then I sign it, the buyer signs and an independent third party (witness) signs it. If the buyer doesn't want to sign then he/she is not worthy of owning a firearm. I have never had a problem with the buyer's when it came to this. Make sure that everyone has a copy.

A background check to retrieve the firearm from consignment should not be necessary because ownership was never transferred. Positive verification that you are the person who put it in for consignment will be required. The shop does have some Federal requirements for the purposes of inventory in order to keep his/her FFL. There is probably a notation for consignment.