I rented a few times at discount cars. 310-cars. Register online, some time they send you emails with promotion code. I never used those codes. But I was told you need to call/book online 24 (or 48 hours) ahead of time to take advantage of those code. Discount has one-two-free weekend policy. But remember to rent at the same location. You can use your gold card for insurance. But you'd better buy extra coverage from your auto insurance company for rental cars - around $3 a month.
Check
http://www.discountcar.ca/English/ you will find different rate at different locations.
Mini Van is the most expensive car.
Good luck.