If you look for long term investment, I suggest investing in bitcoin or ethereum because both of them are great and for sure they will increase in the future, and you will make a good profit by that. If you look for cheap coins, then you should be more careful because it's hard to know if a cheap coin will increase too much in the future or not because the most of cheap coins are not so volatile in the price side, only few crypto will make a high increase but you should always search for these projects and don't miss any good opportunity.