Lots of vacation rentals are not air conditioned in Canada.
I cancelled my summer holiday last year due to the forest fires. 3 of the 4 rentals I had arranged for our 7 day road trip to Muskoka, Parry Sound , Killarney Provincial Park,
Manitoulin Island, and Owen Sound did not have AC. The smoke from wildfires was too heavy for people in my family who are immune compromised. Even the car ride from destination to destination would have been a challenge with the smoke. I had planned the vacation 3 months before. I’m hoping we can do a 3 day getaway later this summer.
It’s possible to buy a portable AC for a couple hundred bucks. Might be worth it! You could always use it for the week, then leave it at the rental or donate it to a charity at the end of your stay.
