I've drawn a few South African buildings in the past, but finding good photos is very hard. I prefer to draw buildings that are completed, not drawing from renderings. Find some good photos and people will eventually attempt to draw them. I just don't have the time to do drawings anymore.
I tried one of them, and an easier one in Chicago. I'm nowhere near the skill level of some of the other guys around here though. Plus I don't have an illustrators account.
Ask Dylan to have an account. Send a PM him. I think he will make one to you when you show your abbilities are good. Ms Paint is a good software but takes too much time. For square things you would like to make fast use MS Power Point as it is easy doing such buildings. Good luck. IF they were in Brazil I could try.