The fact that you describe everything is true. You can also add if the scammer very much praises and advertises his project and promises big profits in a short period of time.
And also if the scammer actions, words or chats are not reliable like they somehow always finding reasons if they will cash out some money. If you ask too many questions they cannot give direct to the point answers. They also have a attitude of beating around the bush of a certain topic. We must know how to choose a legit and true person to avoid scammers.
I think, it's very difficult to avoid a scam, because it all depends on intent. even one person who is thinking of cheating on a project will make the whole company a scam. well, moreover it's very difficult to avoid that because sometimes they initially intend to be serious, but seeing a lot of money makes their project a scam. there are many types of people in cheating, we just have to be vigilant, and experience will make you aware of it.