1. Verify project's viability
2. Verify core team's identity
3. Check if they have a working MVP already
4. Check repository / Github activity
5. Ask the team on related questions on the project's social media channels, etc...
What should hunter do, if the projects passes all the 5 points you wrote, or simply dont have some the points.
It is not a total guarantee that a project is not a scam even if it had satisfied all of the points mentioned above that is why we continue to have due diligence or investigate further about the project.
For example, bounty campaign of an exchange. Do you often see they put their team on public or post a lot in github?
Or MVP - often the team is in a processes of collecting funds, decides to run a bounty campaign. They wont have a MVP.
Well at least they must have a working MVP or else it is highly unlikely that they will ever produce one. As far as I know, most legitimate exchanges are already in operation before they had conducted a bounty campaign to promote their company.
"5. Ask the team on related questions on the project's social media channels, etc..." - I've tried asking CZ questions about Binance in twitter, but he ignore me. If he ever run a bounty campaign, I'd better skip it. They seems shady, except CZ I dont know any representative from Binance.
Binance is already an established company, and I don't know if they had initiated a bounty campaign that could be related to your inquiries but I think you could try other support channels instead of using Twitter so that they can better address your concern. Moreover, I presume CZ is a very busy person that is why we should take such inquiries to their dedicated support team on different media channels accordingly.