These are the files that I use to make my own personal finance application. I created this around 2014 and has been running smoothly ever since.
some of the scripts require keys or paths that you will have to specify. Check out the blog from an archived HTML file
This is the application that gets your transaction emails (GMAIL) and sends them to a google sheet OR to a SQL table. This runs within your GOOGLE APP SCRIPT on your own account. In this case I'm only using SQLServer so the SQL querystring might change for your application.