Great idea! I always do some quick 'back of the napkin' calculations whenever I consider starting a new project as it has been proven very useful in deciding whether to pursue a project or not.

Props for the video as well! I really like the fact you used a real-life example rather than listing the features or simply showcasing the interface. Something other startups can learn from!

Seeing the product made me wonder about two things however:

1) There seem to be quite a few pages. What I like about a spreadsheet is that I have everything in place which gives me a better overview and let's me try out different numbers real quick without having to click through different pages. This is something I feel like the product could prove upon. (I've only watched the video though, so take it with a grain of salt.)

2) You ended the video with $0 funding needed. I bet that wasn't a coincidence, and you planned that making the necessary number changes to arrive at exactly that number. However, you didn't show you came up with these needed changes. I feel like this should be part of the service: let me decide on an end number (e.g. $0 funding needed) and highlight the parts I need to change to make that happen.

Other than that I like the concept. Looking forward to the launch!