Im not a fan of scouts.
Id rather look for a high 5 star player who is one or two points off scout level on the market, as you can then target 18/19/20 yr olds.
Im also a fan of the negs list. Search for players that are 18/19 and play for teams that are a few levels above you, as those players wont be useful to their current owners - but will be the best non scouts for your level. I often get 5/6 good players off the negs for the price of a decent scout.
Scouts simply arent worth it in my opinion, even with thousands of tokens I wouldnt buy them unless it was a last resort.