You may want to try
www.trustedpros.ca It's mostly a residential contractors website but lots of the contractors on it also do commercial work. It's a different dynamic than kijiji or whatever because you are posting a project and the most motivated contractors contact you wanting to bid. Works really well. There are performance reviews so its pretty easy to get a decent read on the contractors that respond to your ad. I posted a painting job on Thursday morning and had 4 bidders lined up for Monday. I had to suspend the ad by mid afternoon because there were too many respondents. Three of the four showed, all on time, and I have the bids already. Good luck.