OURS-project: Step-by-step instructions to build a smartphone that is open-source, upgradeable, repairable, and Big Tech free.

Nice DIY project. But if you just want a phone, i'd probably recommend a pinephone.

That’s the total cost of the parts (according to the part list file):

Total: R 3,639 198 USD 180 EUR (27 April 2023 rates)

I think you can flash some android OS's on the rPi, OmniROM is listed as an option, so it could be a better starting option instead of raspbian - https://omnirom.org/

Nice work and project! Will follow.

I wish I was that smart, congrats