I think the total cost ended up at around $600, but I really tried to cut down the costs, bought a second hand screen, arcade buttons/joysticks from Aliexpress

I think the total cost ended up at around $600, but I really tried to cut down the costs, bought a second hand screen, arcade buttons/joysticks from Aliexpress etc. I also have access to a really nice workshop which of course helped a lot. Ohh, I don't know, but that sounds like a really interesting project! Mount IR sensors in the cabinet and connect them to the RPi. But I'm not sure about the integration with RetroPie or similar softwares.