Yes. I tried in one of my rentals in Toronto. It was 2 or 3 years ago. It worked and still working well. They drilled a couple of holes in the corner, I do not think they put any gas inside. I think it is a kind of natural ventilation, but I am not sure. It was an inexpensive solution which...

I charge $35 for NSF. The amount is clearly stated in my agreement. I collected the NSF charge in the past with no problem so far. I am in Ontario.