Two weekends ago I was doing some practicing and lessons for a friend in the Oakville Place parking lot. Saw the security guard and asked first. Was told to finish up the practice by 9:30am and it was even suggested to use a specific lower lot because it was the least used and most level. It was perfect and we got 2.5hrs of non stop practice in.
Last weekend I took two other friends to the parking lot at John Fraser high school in Erin Mills - this time at 6pm on a weeknight. Parking lot had cars coming and going and it was also smaller and dirty so I wouldn’t go back there. Across the street I could see huge empty parking lots at Erin Mills Town Centre, but figured we would have been kicked out of there for sure.
If anyone has other suggestions for lots in the Mississauga or Oakville area post them up!