That's where it gets tricky.

A mobile refrigeration certification is laughably easy to get but in most areas, city and state codes, to be 100% in compliance you will also need a recovery machine and some fashion of leak detection equipment. They, recovery machines, are getting cheaper but the last one I bought, for commercial building use, was almost 2 grand. A vacuum pump is also another necessary tool, nitrogen cylinders and manifold set is helpful as well.

There is a reason most shops charge the bucks for A/C work, lots of fancy and expensive equipment is required.

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Chas

Had a 380SL, 450SL, 380SEL, 420SEL, 500SEL

Got a Euro 500SEC right now.