Don't buy a trainee until the next season starts. Otherwise you will only have the luxury of training a good 18 yo for 6 weeks or so. If you wait until next season you can see if you get any luck in the draft and also have way more quality training time.
Only have the luxury of a good 18yo for 6 weeks??!!! Most teams would die for that!! To the original poster - let me make a guarantee. The money you have now will stretch much further than it will if you try to get a brand new draftee. You can buy decent perennial even allstar potential players at age 19 and train til 23 and create great players. For a team in your division you could do a lot worse than to try and spread the money over 2 trainees and maybe sacrificing a skill or 2 here and there.
Just another opinion you may like to consider!