I'm adding on to my home and I decided to run the addition on a tankless 4GPM,,, It came with 1/2" Input and out would it be in my best interest to stay 1/2" all the way or go to 3/4 after the water heater and split off with 1/2" at each faucet,,, the addition containes a master bath a second 3/4 bath a kitchen and Laundry room,,, I'm torn between thoughts Hop someone can help me,,,,