How much did that reimplementing cost and when will the savings exceed that cost?

This costed around $10k. Which also includes work that is outside the reimplementation.

I do not know how much actually cost of the original application.

The app, that I was developing, was for another purpose, and the reimplementation was later added.

The app replaces an existing commercial app that is being used, which is $200+/m. So, may be 4/5 years to exceed the savings. They have been using the app for 3 years, I think.

And, maybe I am beating my drum a little, I believe my implementation works, and looks much better than the commercial or the first implementation.

So, I am really looking forward for this to success.