all these pictures show both hangers being used as far back as 2009..so I dont think WM had any type of airline business going on for quite some time. Living with his son and working along side him, how could he not know what was going on, unless it was truly a hobby until he died and then DM not having a clue what to do with the airline business figured he was going to have to make use of this new hanger in other ways. I just dont get how someone didnt see something, even the Waterloo airport manager saw non aviation related vehicles in the hanger when he met with him weeks ago..would you not question seeing 100 vehicles inside the hanger and notify police?
Generally, as long as the business appears to be legit, and they are continuing to pay their bills to the airport and not causing issues - what the occupants/tenants/owners of the hanger do with their space, is their business.
I come from a light aviation background - i don't have a plane or hanger myself - but a close relative did - even a small hanger is a great storage place for large bulky items like flatbed trailers, bicycles, motorcycles, lawn mowers, additional aircraft in pieces, etc.. anything that would fit around the aircraft without posing a hazard to it, is/was fair game as far as the hanger owner/airfield owner is concerned.
The airfield owner/manager is really only interested in the monthly rent on the land that the hanger is built on, and that your activities aren't posing either a H&S risk, or a risk to other owners/operators on the field. Nothing more.