your aims are a bit high for starting it would cost about 50,000 to equip a workshop but without qualifications you would never get public liability insurance and your repairs would not be considered adequate by manufacturers, rebuilding transmissions is a very skilled job again without qualifications who would buy your transmission, one failed transmission would put you out of business, if you had the money you could employ qualified mechanics and get some diplomas on the job
a; go to mechanics school and have all your skills testedb; work for another shop for at least 3 yrs so that you learnwhat other proprietors do effectively and poorly.luck![50k just for equipment, not counting salaries, overhead, etc.]
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