Don't forget the battery, leave a 'normal' battery through a few months and it's dead. What happens to a normal car once all the fuel is drained? Coolant? Oil?
How did these design flaws make it out of engineering?!
You can comfortably leave a regular car alone for 6 months and when you return at worst the battery will be flat and there'll be some rust on the brake pads. I regularly do this to my poor old diesel SEAT. Even if the battery is flat I can either bump start it, or worst comes to worst, buy a new $50 battery.
Diesels are a fair bit more tolerant, and low end cars are actually much more robust than performance cars. Try leaving a dodge viper unattended for 6mo.
I drove a diesel land cruiser (lm78) which had been sitting on an airfield unused for years. Aside from needing tires and a battery (and wiper blades) no problem. Even the fuel was ok.
How did these design flaws make it out of engineering?!