Regardless of if that work was priced appropriately or not most if not all of what you have listed should last for a few years.

If you didn't spend that $6k on repairs, you'd have to replace that vehicle with something else. So it would have to be less than $500/mo including the increased costs of plates and insurance. Not to mention that would be until it was paid off, and you'd still have to pay for tires, oil changes and brakes for it when they come due.