Alexandria, Rigaud, etc. as well, although I'm not sure about day rates. There is a large trucking population - with a big truck stop near Vankleek Hill that probably has short-term berth areas.... if you want a trucker pod.
I'd say Casselman or Rigaud would be your best bet, although they're not at the mid-point.
If you're teaching a class and can't find a day rate, best bet would be to see if they have a meeting room.
Edit: And then I realize that I'm a day late...
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