If the price is OK (not extremely high), I'd still take the plunge and gamble it. If a young player doesn't work out, we can still sell him, if he works out, we hit the jackpot like Madrid did with Vinicius. Much better than buying low-risk old players in their 30's in my opinion.
These guys rarely go below 30m. Those 30m can buy you a Koulibaly.
Will take a few years before we are able to invest 30m in future signings instead of using it right away.