Well.... my Dad used to be a mechanic for a Porsche dealorship in Europe.He has over $50,000 in insurance for his tools.His most "valuable" tool, is his hydraulic lift in our garage. It rasies the car 4 feet high with the press of the button, and is made of stainless steel. It lets us do anything and everything that needs to be done to my car, from putting my exhaust on, to swapping an engine, to changing the oil.Congrats on being a mechanic though! Even though I'm in Medicine, I think being a mechanic is far more difficult. Just think, the human body changes every 1 million years, while an engine is revamped every year! And don't get me started on the complexity of cars (though I'm sure most of you know

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*EDIT*Here's some must-have tools I thought of:-Battery voltage checker-Oil filter wrench-4x4 feet stainless steel pan (for removing the block and letting fluids leak onto)-Gasket scraper
That's it for now... too tired!