We just had the ATF Inspectors come by for a talk
And one suggestion they gave is that you may want to get two safes. This is to prevent commingling between your personal guns and those belonging to the business. If they're commingled, the ATF inspector can look at everything.
One is for your personal collection. Unless there's a warrant, you don't have to open this one for the ATF.
The other is for the ATF Inspection. This one must be opened and their contents examinated upon their request.
Vigilantibus et non dormientibus jura subveniunt. Molon Labe!