It's different between new coin and famous coins such as ethereum, dash and monero. If you want to invest in potential coins, don't worry to invest in those potential coins as it has been proven reach certain price, as long as you don't buy it at the peak. But, if you're looking for cheaper coins, it will be more tricky, the criteria has been mentioned above such as devs team, idea of those coins, road map, and how it will be developed in the market for long term. The problem is, there is no guarantee if those coins could rise instead of dumped after listed on trading platforms, you have to be patient and waiting for months after buy new coins on pre-sale or ICO.
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