Hi Felix,
To be honest, we want to be as flexible as possible in this regard.
A team can consist of as many people as you want, with overlapping team members among teams.
Each team can send as many solutions as they like as long as they are distinct in their approach and not simply multiple attempts using variations of the same method. If you end up performing multiple attempts using the same method, you should just submit what you believe to be your best attempt.
I hope this helps. I am just not entirely sure what you envision when asking this question about the "maximum number" of submissions.
Cheers,
Aidan