As I mentioned, the most important thing is to get a rack which will easily let you lock the bike frame to it, not just the wheel.
Here's a handy guide explaining different considerations: https://s3.amazonaws.com/BikeWalkNC/Docs/NCBikeSummit2013/Presentations/Bicycle+Parking.pdf
The cheapest / most common option is a sheffield rack (aka staple rack).
Here's what they look like:
They probably go for about $50-60 CAD per bike: https://www.broxap.com/sheffield-cycle-rack-2.html (This is a British site, but I'm using it as an example)
Another moderately priced option is this guy:
For example, Cora Canada sells the Expo W7510 that supports 7 bikes
http://www.coracanada.ca/products/
They don't publish their Canadian pricing, but I found their Austrial price sheet: https://www.cora.com.au/assets/downloads/Price%20List.pdf
According to this, the rack for 7 bikes might cost around $750 CAD plus tax.
Another supplier for the same design as above is **Dero, **and they call this design their **Campus Rack. **http://www.dero.com/product/campus-rack/
According this 2011 price sheet I found, they were charging around $600 CAD for the **S6 model **which parks ~10 bikes. Again around $75 per bike then.
Finally, the most space-efficient and convenient design (according to my bicycling enthusiast friends) is this model by a European company called Velopa
http://www.velopa.com/productcatalog/bicycle-parking/tulip/
It's advantage is that it both holds the wheel AND provides an arm to lock the frame to. Also it alternates the height of each bike, allowing you to put more bikes in the same small space. It's definitely more expensive, as according to their Belgium pricing page, charging around $220 EUR per bike. This is three times as much, but it's style, convenience, and space efficiency might make it worthy of consideration, because at the end of the day, the one-time price of the racks is nothing compared to the rent of the room.
Here's a great page with additional Canadian and USA suppliers:
http://www.bicycleparkingonline.org/Resources
Once we decide on the design, dimensions, etc, we'll need to contact a number of these guys and get quotes. Unfortunately they don't seem to want to list prices publicly.