There is a multiple car discount. And yeah, that "pleasure" car discount can be pretty big. Find out how strict your company is about checking. My agent is supposed to verify the mileage on our "pleasure" cars, but he just sends out a letter every renewal which we ignore. He then proceeds to forget about it too, even tho we may talk to him several times during that renewal period.
Once you find out, then put the more expensive to insure car as the "pleasure" car if possible. A good insurance agent will work with you to lower your rates as much as possible.