Yes, before joining a project You must look at the White Papers and see their team LinkedIn profile correctly. You will get some information about the project to some extent. What do people do with this project and what have they done in the past? All in all, it is important to get the right information.
Plagiarism checking of whitepaper will make sure you avoid the scam projects. But this is a difficult thing to do because of lack of such softawre available.
Also when you do background check on the team members, make sure to properly do a check on their education background and if possible contact the college or university about their alumni. Many times scammers will make profiles just as placeholders but these are rare on LinkedIn but it never hurts to check.
Before joining any bounty, do good research and assume that you are going to invest in it.
It is better to assume that you will not be getting paid for your work. It is what the reality of the bounty hunting in this forum has been for years now.