Carrying on private business

[Quiet]

having

Not sure but I think this is regarding possession = having, as opposed to carrying.

"Having" means "having access to".
"Having" does not mean carrying.

[Chewy65]

See the Overturf case holding that while an apartment house manager could have a firearm on his property he could not carry it in the areas open to the public

[Cokebottle]

Bingo.

And also keep in mind that if you are specifically hired as a "guard" and carrying a gun is a condition of your employment, San Bernardino will EITHER deny your application, or if you have general good cause, they will issue, but the permit is marked "Not valid for employment purposes"

If you are a salesman and carrying is not a condition of your employment, then you may carry for self defense using the SB permit.

Re-reading some of these posts, it sounds like you are skirting the line (if not over it) of carrying being a part of your employment (my initial perception was that you were already employed and the boss wanted you to start carrying)