My Prefix works solo,My infix will disagree,
My suffix is the end, now tell me where I be.
I think the answer is:
Monopole or monopoly
Mono = one, single, only so it could be considered a synonym of solo
Nope = as a disagreement
Pole = like North or South pole, i.e. the end of the world, or the end of the Earth's axis.
So you are either on one of the poles or you are in a game of Monopoly, maybe?