These are good pointers and pretty much covers the whole thing about what to do before the investment.  Though I would prioritize the team capability than the proposed project.  Also, if there is a way to verify the said achievement, skills, background of the developers, it should be the very first thing to do.  Anyone can claim that they are a master of this, supervised or done millions of projects, so to make sure that they are telling the truth, it should be verified through Background investigation that includes inquiring on the list of the institution they had stated.