Serpent said:
In my experience, Enterprise is reasonable + they'll pick you and drop you off after the rental is returned.
One thing you might want to check is if your CC has rental insurance that covers collision and medical. If so, do not buy the rental company's daily insurance which can be a significant amount.
Check with the company you buy your auto insurance from, or any insurance company for that matter. I don't know how it works in Ontario but in Manitoba you can buy rental car insurance from MPIC (gov. run auto ins.) for a fraction of the cost of the rental companies rate. Usually works out to about $4.00/$5.00 a day, or less, depending on the length.
I usually use Enterprise as well, used National a couple of times and all three times the cars were filthy inside when I picked them up. Every complaint was answered with "Oh, sorry about that" nothing more.