That is quite a hard question @OP.  No one is sure what the price of a certain altcoin is in the next 5 years but if you are so eager to invest, I can say try to look for an altcoin that has a low price, solid foundation, good community, and had been running for some time and yet been pumped hard.  You can try to look for a good altcoin that is less than $5 in price because the lower the price of an altcoin is the easier for its price to go up and the profit multiplier to ramp up.

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