I have been thinking about adding a front and rear camera but all on the solutions I've seen so far questionably compatible with e89 or extremely expensive. I just ran across this one on ebay.
https://www.ebay.com/itm/26328289553...534#vi-content
Their website has a bit more info.
https://www.peem-solutions.de/rvc_emulator
Has anyone installed this unit and what were the results.