ISO – Plugin 2 track job progress (car hauling) – possibly project management?

I have a client that hauls cars. He wants the ability for the car’s owner to log in and view notes on where the car is currently, and the estimated delivery date (etc). He wants to help ease the amount of phone calls he gets daily.

Does anyone have any sort of plugin type in mind that might work for this? I don’t think they need any fancy fields. I’m guessing unique user accounts, the ability for the user to see only their ‘notes / updates’.

Thanks!