>>287735573
>just something that could provide me a mildly superior experience to using my phone in a Cardboard
You mentioned "VR headsets get overhauls so often that I want something upgradeable and cheap" so I assumed you were talking about headsets like the Rift or maybe even Index and wanted to build something like that except you could have the advantage of switching out parts. But since you're goal is actually really low, then sure, it's definitely possible to build. I would just not say that wanting something "upgradeable" should be part of your motivation, simply because better than Cardboard and PC connected still isn't really good enough for doing much.