Why 4 or 9 Ending Quality?
Because that appears to be the strongest players on the market if you order them by quality and that's where people usually go crazy and spend tokens.
A lv 1 would be trying to get 24Q players
Lv 2 would go for 29
3 for 34
4 for 39
and so on.. as this is the best you can get from the transfer market.
I know Academy grows slow in the begining, you would have to upgrade your stadium and you'll slowing start to earn cash.