Here’s the spreadsheet I used (web version w/o formulas; [https://docs.google.com/spreadsheets/d/e/2PACX-1vRNuWRCNyNxRnYu-gwHe_8OQXI-Omr9QWW3IB8GyPGP_5W69yh73u1wXw5dZgh5Mc4y5KYfzAnsPFfW/pub?output=ods) (LibreOffice native format w/ formulas). This exercise was motivated by this video by Ben Felix.

It looks like I was calculating rent increase incorrectly (only increased one year), so I fixed that and the total was below the house value. However, I also wasn’t accounting for maintenance, so I added that in at 1% of house value per year (this article claims 1-4% per year, and the numbers are about what they were in my original post.

Here my calculation for investments while renting (I’m using monthly compounding):

FV(10%/12,12,(mortgage - rent)+(house maintenance/12),investment value)

Investment value starts at the down payment, and otherwise we’re investing the difference between the mortgage and rent as well as how much the home owner would be paying for maintenance. There are still some things not being accounted for, like renter’s insurance, home insurance, taxes, etc, but I think those would favor renting as well, so I left it to a configurable percentage of the house value. You can play w/ the spreadsheet by using a fixed value (i.e. if you’re into DIY), adjusting the percent, changing borrowing rates, etc.

I compared my calculations w/ this investment calculator to make sure I did things correctly.