Need advice on Outdoor advertising!

Hi guys,
One month ago while driving back to my home I noticed a new billboard placed in front of the mall. It shared a meaningful message which was really impressive. The message influenced me a lot and I realized that it is one of the effective methods to target audience for brand promotion. It also frees up our time on investing in other forms of advertising media. I’m considering to approach a service that does outdoor advertising in Toronto.
If anyone here has done this in the past and would like to share your insight I would greatly appreciate it.