08 nissan rogue coil bad in ac compressor

You most likely can replace the coil yourself but the clutch and pulley has to come off and would require a snap ring remover set, holding device, and puller. I don't know how accessible that compressor is to service. If the compressor itself is bad then you would be wasting your time just replacing the coil. As far as doing the whole system the refrigerant would need to be captured and the system pumped down. Other parts such as the drier, expansion valve, and condenser should be replaced since that is where blockages happen. Unfortunately some shops have a shotgun approach to some repair jobs or don't feel that won't make enough money off a job. 2k for the job does sounds high but guess they have high overhead costs. Hopefully you can DIY and add some tools to your collection. Good Luck!