I have a avov hybrid box that already has a subscription. Is there anyway of finding out who the subscription is with? I did not put the sub on it. It was already in it.

Hey guys I'm new to all of this and am looking for some help to get all set up. I am currently looking at the avov box and am wondering how much is a reasonable cost. Also who and what do I use for a server? Who's the best of offers the best? Thanks