As already discussed above it depends on the financial capacity of your senior club. If you can not afford that 10k€ then look no further, invest only 10k€.
Otherwise at the beginning it's quite simple : if you can take 3 recruiters while investing 20k€, then do it, that's the most profitable.
Invest therefore the maximum but within the financial capacity of your club.
Scouts all have the same quality so there is no trap. For their location too little is known to advise anything so do not be afraid to test and change if you feel the need following poor results.
In any case whatever you choose you can get any type of proposed player, and of all qualities. You will only change your chances of finding a particular type of players with a specific search.
Enjoy if you prefer a particular type, you will increase your chances of earning good young of this type.
If you have no preference at the beginning choose "Any type of player" which gives the best chance to get a good young (of any type against).
Once you've pulled a first good young player, scout for his particular type. So you can expect a massive and effective training if you succeed to fill the corresponding line-up.
Scouts give you comments always about the best 3 skill potentials of the player :
From time to time they give you an indication of the player's overall capacities.
This will therefore give an idea of its type even if the profile is incomplete.
It is a difficult question but I'll give you some things to help you :
My final advice : do not be too demanding at the beginning (although it should not fall into excessive leniency). Gather all the best criteria is quite rare so do not forget that when you start you have to recruit young people to train. There will be a waste whatever you do. Some young people with medium comments can be very good. Sometimes there are enough pleasant surprises. Give you that chance rather than risking not to recruit any decent boy after 10 weeks of drawing.
You will learn to find balance between the refusal to try another scout and recruitment of a young even uncertain on 1st scout. It is learning to do and experience to get to become a good manager. You'll also learn to adapt your recruitment according to the state of your ever-changing workforce.