First adjust your arena prices when you can:
BL: 13
LT: 40
CS: 115
Also should consider expansion when funds are available to raise future income.
As far as players go:
I only see one potential trainee but even he seems to be onsale.
I would sell my 18/19 year old trainees with under allstar (6) potential
Buy 2-3 18 year old trainees with similar height and potential of at least Allstar
Keep 5 of your better players to play in league games, sell the others
buy cheap backups to save on costs. You will lose some games but you wont go bankrupt.
Also when your trainees get a bit older you can sell them for much more than you will be able to the ones you have now.
You're in a tough position but I would first look at how to cut your costs and then build up your arena so that you can afford better players. Also maybe look at getting a cheaper doc/trainer/ PR (though pr brings in $ so use discression)
best of luck