As a buyer, you would need to decide for yourself whether you want a guaranteed working firearm or not.
And in many cases, the owner will test fire the firearm before putting it on auction anyway.
Old Martini Henri rifles, dueling pistols, even muskets in some cases.
Source: Forgotten Weapons and Royal Armory youtube channels
...And modern replicas tend to be safer when you pull the trigger.
https://forums.somethingawful.com/showthread.php?threadid=40...