use in recreational vehicle

You don't need to pay extra to use DirecTV Stream anywhere. You just need a streaming device that can use the DirecTV Stream App, like a Roku, FireStick, iPad, etc. And a reasonably speedy internet connection. 

Just to clarify ....

Do you have DirecTV Satellite at home or DirecTV Stream service?

You would need a SWM dish on a tripod or sled mount and learn to aim it or get the more expensive self aiming ones from Winegard or KVH plus whatever channel package you want but there is no discounts for having both.  Once you get outside of your local channel beam you will lose all local channels.