https://3dbag.nl/ might be worth a try. This project reconstructed and maintains building models of 11 million buildings in the Netherlands.

It combines airborne LiDAR and building footprints, it's OS (https://github.com/3DBAG) with the reconstruction pipeline here: https://github.com/3DBAG/roofer.

Great story, thank you for sharing!

Your mom was awesome :)