Hello, Labor time to replace the A/c compressor is 1.2 hours plus .6 to evacuate and recharge the system. A remanufactured compressor is around $350. 2 pounds of r134a refrigerent will cost about $40.
They sell, do it yourself kits to add refrigerent, but I do not recommend it. For a system to function properly it must be vaccumed with a special machine, to remove moisture.
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I hope this helped if so an accept is appreciated