We recently took a mortgage on our house. As I am self-employed, there is a lot of variability in my income. So I wanted to see the impact of occasional top-up payments. Most online calculators couldn't tell me how it would impact my loan term. So I went ahead and built an Excel calculator to give me the answer.
In this video, let me tell you the story of that and walk you thru the process of building such a calculator yourself.
0:00 - Why I couldn't use the existing mortgage calculators
1:00 - Quick demo of my calculator
2:00 - How to build such a mortgage calculator yourself
3:36 - How the "extra payments" work
4:19 - Setting up the loan amortization table
10:34 - Adding the bells & whistles (chart & conditional formatting)