Using Roamio OTA DVR for 4 TVs

I'm trying to understand how to use Roamio OTA DVR as my source for all local tv. I have 4 tvs in the house.



Do I need 4 Roamios or can I use one and 3 Tivo Minis? (I have cable connections between them all now for a Dish Network setup so I can reuse that).



Thanks in advance,

Mike