lvl 4 trainer it's ok for the moment, maybe in future, when you will have some money,you can try to buy a lvl 5 trainer.
about PR manager it's up to you...if you know that you will win a lot of matches, you can hire a lvl2-3 PR manager, and don't spend money on lvl4.
Doctors...
Is this a good enough doctor? Will the doctor help reduce that 2 weeks now that I have him? If so, how much will it reduce it?
first of all you must know that:
The doctor also heals your player faster since the new staff system. So a higher level doctor surely pays of. However the most important part of the doctor is still making sure the player won't get injured
more information,you can find here
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