Here is the real answer from a Torontonian who has traveled to SG extensively.

Don't let the outside temp scare you, in winter all indoor facilities are heated to 20-22C. Think SG: all buildings are aircon from the heat and humidity. Heavier pants and a good outercoat is what you would need.

Are you business or pleasure or visiting relative? big difference lah!

2) Normal meal in Markham, it is like in SG hawker vs fancy meals, if you go to the Asian shopping mall food court it would be 7-15 lunch 10-20 dinner. There are expensive restaurant as well with many different ethnic cuisine.

3) Markham is not easy to get taxi. Plan ahead and call/book or use Uber.

4) Yes for Markham, it is suburbia, a car is a must for getting around. If you are driving in Sg you should not have too much issue aside from the "side of the road".

5) Parking lots for visitors to buildings and shopping malls are free.

6) Taxi or airport limo from YYZ to Markham town centre would run about $75 plus tips. If you are renting a car it is best to pickup car at airport and return it on your way home.

7)I have two mobile plans, one with national branded carrier, expensive but reliable. I also have a low cost limited coverage area plan cheaper but not as reliable. Bell Telus and Rogers are the three main big carriers. You can check the travel tech forum for Canadian SIM for visitor data usage.
http://www.flyertalk.com/forum/trave...im-canada.html

PM me for more info if needed.