It's easier to look at this scenario if you realize that all of this was done before any description of the suspects and especially before the information about the tattoo was released. I'm surprised actually, that LE didn't spend a few days following him around when they got the tip about who had a tattoo like that to see what he would do and what he would be hiding. Or maybe they did? But it appears that they arrested him as soon as they got the tip about who had that tattoo.
And I suppose we don't know what type of criminal behaviour DM may have been into prior to this. So if he had been getting away with things in the past, tied directly to his own properties, then he had no reason to believe he would be caught this time. I'd say he was definitely a thrill seeker. Makes perfect sense that he would hide things on his own property. No one would be able to look there without obtaining a search warrant or permission from him and he had no reason to believe that anyone would be looking at him. He also would have to have some time to slowly dispose of evidence without drawing attention to himself or his accomplices. I think he panicked with the truck but figured that no one would be making a connection between Kleinburg and Brantford when looking at this case. Leaving it at the hangar in Waterloo was just too close to the crime. And it had to have been somewhere before it got dropped off at the mother's house. That tattoo was his downfall. And even he likely didn't realize that the person from the previous test drive would have noticed and remembered it. Especially if he was wearing a long sleeved shirt or jacket.
I think DM has been spiralling out of control for some years. I think there is drug use, rave parties, people who are "hangers on" and an overall sense of entitlement. He didn't want to run a business. He wanted to enjoy his life with the money that was already available to him through the family assets. Spoiled rich kid. Who attracted the worst of the worst no doubt to "play" with him. His father must have had issue with the way things were going in his life. Can't believe he was that complacent about the activities at the Toronto hanger either.
MOO
