I read this when looking at migrating: "We are working on supporting migration of Heroku apps that use multiple buildpacks." -- https://render.com/docs/migrate-from-heroku#fnref-2

I guess I would need to place the extra node steps and python build steps into a single build file and then point the render.yaml at that custom script? I wanted to tell from the docs if it was possible before even starting on a prototype to demo it. Is there an example app that fulfills this. Thanks for your time.

Exactly, you can use any command or script to build your app, and you would select Python as the native Render environment and run your Node build as part of your build script. Here's a quick example: https://render.com/docs/deploy-django#create-a-build-script