Windsor taxi is expensive, normally from any mall to university area is about 20 $ single trip. When you shopping there is no bus, you have to pick up taxi when you have many things. But most taxi drivers are OK. And they come in time.
If you want cheaper price, you can go commercial column of our site , there are many students and other Chinese people there who have car will offer you cheaper rate, normally only around 10$ to 15 $. But it will depend if they have time. I called many times but they are all busy. So taxi is still a good way to shopping . You can go with bus to save one way money. Or share with many other to save.