I am a big believer in not re-inventing the wheel. Is there an app for this? Does someone have a spreadsheet that they like? Is there a good method for adjusting the various options to see how it comes out, or do I need to spend some quality time with Excel for the next few months?

Have 401ks, cash, home with $500k in equity, custody of two kids, two cars, and a thousand moving parts here.