I too recommend Mastercool. It's what I have, and I think I paid about $200 for it. For my purposes (vehicles and occasional appliance or home HVAC use) it is perfect. Robinair are nice but a little pricey.

Whatever you do, don't get one of those venturi vacuum pumps. In my experience the vacuum is so weak that they are only usable when it's 100 degrees outside AND you have the engine running with the hood down generating as much heat as possible (to aid in boiling off moisture). Plus they can take a year or two of life off your air compressor...

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280