Looking for a mobile DVR to make a custom modular system

[danielisgreat]

Looking for a mobile DVR.

Pretty much mandatory stuff:
GPS
3+ channels
Always on / precord event buffer / event trigger (motion, G shock, etc)
64+ GB
Automatic overwrite of oldest files

Preferred:
WiFi
128+ GB (with 2 storage units)
Local network access / streaming
Waterproof, able to be installed in engine compartment
4+ channels
1+ audio channel
Common video input type
Low voltage shut down



Thanks for your input!