It is way more prudent to just avoid buying icos at all, I know that many people do not like the idea of stop doing this because they want to obtain great profits in a relatively short amount of time, but when you see the huge amount of scams going on and that despite the efforts of some trusted members in the community exposing those scams you see new ones appearing every day then it gets very discouraging and I do not see how we can invest in icos when all confidence in them has been lost.

But if you want to do it the only thing that I can say to you is that you do your due diligence otherwise you will be relying completely on the developers of the ico which are the last persons in which you should rely that much.