Never ever start any project without financial closure. Short term approach that lets manage till we need additional money invariably will puncture (Cost and time overrun, cost of finance will go up in a emergency situation and not so well thought out decisions in desperation) the project.
Don't forget the lesson of 2008 crisis, take money when available and not when u need it. You may not use the available money in full and pay interest or commitment charges , but that is a better scenario than no money and project suffers.
Seen this and seeing again and again.
(Not appliable to start ups, they need to manage from whatever sources till they dilute to professional investors)