Working on a client's long term loan with variable interest and some irregular payment timing, and I want to build out a proper liability amortization schedule that captures principal reduction, interest expense, and the remaining balance month by month. I've actually usually used Excel for this with basic IF formulas and a running balance, but with the odd payment structure here, it's getting messy fast. Anyone have a template or method they like for handling non standard loan terms? or how I can go about laying it out clearly when the payments don't follow a clean monthly cadence?