You would probably need 2 Hoppers and 2 Joeys for your needs. That's going to cost you a bit more than you were quoted, monthly as well as up front cost. Don not, I repeat, do not even consider a single Hopper 3 Joey configuration. You already have 4 tuners with your 2-722 setup, you only have 3 tuners with a single Hopper. That said, it would easily be worth it go with the 2 Hopper scenario.
So how many tuners with 2 hopper configuration?