Airsoft gun longevity
I'm looking at buying an airsoft gun off kijiji, but the gun is used. How many BBs/how long are most airsoft guns rated for? The gun is a full metal SRC M4. The seller says he's used it for about 10 full day events. To put this in car terms, I don't want to buy a 1988 rust bucket thinking I'm getting a 2005.
Thanks for the help and advice in advance.
EDIT: I posted in this wrong section by accident, I apologize.