Dish Now was/is a pre-paid system that was still working this last summer but I dont know if I can still use it. I would go to Walmart and buy a Green Dot money card, call Dish and tell them how many days worth of Dish programing I wanted. I own my own reciever.
I liked having the dish now box for the cabin. I could use a $30.00 card and have TV at the cabin when I was there. Paying for 3-4 days at a time.
Now with Dish now being dead IF I stay with Dish because of the crappy DVR double dipping I'll just grab a receiver from home and bring it back and forth.
I'm curious if you have any trouble moving to Flex or a full subscription on your old prepaid receiver as I have one I haven't been bothered to convert.