Ask to talk with their previous co-founder

[_ot2g]

I am always looped into conversations that are asking about 'what you wish you've asked your co-founder before you started', and the most simple answer is – ask to talk with their previous co-founders.

Whether they will let you talk with them (or have an excuse not to), what they will say, etc. is going to be a huge telling card about what you are getting into. Don't skip this step.

[psyklic]

Also: It would be wise to verify their professional references. Diligent VCs will check them when you start pitching, and your co-founder's poor references will hinder you from raising capital.