Well you need to be cautious even about small details when it comes to your money. Sometimes its enough take a look at the webpage of a project, how much was spent on design to tell right away if it is a scam. Others are more elaborated, then it needs time to check the facts, ask right questions, watch for scammers to uncover themselves.
In white paper I usually look at the market of the project, its scale and turnover, business model, how profit will be generated. The more specific facts they provide the better. The team, past experience is necessary, otherwise my participation is unlikely.