In the face of too many scam tokens/projects,here is a philosophy that can be helpful, quotes below
"All tokens/ICO/projects are worthless until you can provide beyond reasonable doubt that they have value "
If you can do that for any project, chances are high you won't be a victim of scams.
What is your own philosophy?
I think community decides on the prices. There is really no value behind any coin aside from what people put on it. If everyone decides a coin worth 20$ each than it will worth 20$ each and if they believe its 2000$ each than it will become $2000 each. So, if you want to make sure an ICO project worth more than its ICO price or not just check the community, if you see the number of people interested increasing every single day than you are going to get a good coin but if you see not so many people talk about it than you are not going to get a good coin.
There was this token about time or something that put advertisements EVERYWHERE and they did not worth anything because I saw their facebook page and only couple hundred people wrote on their facebook. However there was IOTA that really put the numbers into perspective because I saw thousands of people writing on their facebook and many other places. Just check the community and in the end you will see the true price.