I take it that you can store inventory at another location also without that 'other' location being licensed.

(C3) May one license cover several locations? [Back]

No. A separate license must be obtained for each location. However, storage facilities are not required to be covered by a separate license, although the records maintained on licensed premises must reflect all firearms held in the separate storage facility. Firearms may be shipped directly to separate storage facilities as long as they are properly recorded as an acquisition in the licensee's records.

[27 CFR 478.50]

What qualifies as a seperate storage facility?

i.e. If I need to take a gun home over the weekend and do some stippling work on it in my garage shop and throw it in a safe there is that kosher? Or since I'm "working" on it do I need to get a seperate license for that premise?

If all you do is store guns or do non-manufacturing work on guns there, then the separate facility does not need to be separately licensed. The "licensed premises" location defines where you are authorized to conduct transfers of firearms, other than gun shows in your state as defined under law, and where you are required to conduct your licensed manufacturing activities, if applicable.

If your "working" isn't manufacturing activity, you're OK, otherwise you need to do that "working" at your licensed premises.

My local ATF agent who does the interviews made it "crystal clear" that I would be in hot water if I stored firearms in an off sight location without prior approval from her and physical inspection of said storage facility. Then she commented the storage facility would need to be accessible for FFL inspections.

I think she was just giving me a bunch of BS. Anyone have any insight?

The notification part and prior approval and inspection part is rubbish. The last part is true, that the storage location is subject to inspection.