I don't believe in keeping things in the house that are off-limits. Audio/home theater equipment is part of the home and for the entertainment/use of anyone in the family. As long as it is handled properly, there are no restrictions for its use.
The cars, on the other hand, are a different story...
Same way my father treated me. The home theatre is in my setup. It isn't audiophile as much as consumer..but still there :) I mainly got to where I am by tinkering with things..not tinkering as I didn't want to break it(though my dad said it was "ok) but because I was astounded with how they worked :) You are doing a great thing!!! IT was truly an experience that was awesome! My childhood was thus filled with technology, however the downside was social isolationism caused by myself. I have lots of friends...lots..but none that I am close to as I am just too different. Anyway, personal experience.
We don't have any expensive cars and the only other things worth a lot are off road vehicles of which we have a plethora of. I do whatever on those babies as well :)