It's amazing that they could take something as simple as the battle factory and fuck it up beyond recognition.
At first it seems reasonable: rent 1 of 3 pokemon and team up with two partners for three 3 v 3 single battles. The problem is that you don't get to choose your partners, they are rolled randomly. If you don't street pass with people your partners are locked in and you can't replace them until you win(afaik, there could be a shop / passage of time could help)
When you lose the battle, nothing changes. Not your rental choices, your partners, not even the opponents and pokemon you fight. When you win the whole round, your rentals and partners get reset so that you can't ever keep a good team either.
As you rank up, the level of the pokemon you rent and fight get higher. Those shitty two partners that tag along with you are stuck at lvl 50.

Fuck the battle agency. Pic related is the only bone the game throws you. You can pay 10 FC to reroll your rental options a limited number of times per day.