what problems does it have
Two good sites to find info on this are listed here: http://www.mycarstats.com/auto_Complaints/KIA_OPTIMA_Complaints.asp Also check out www.carsurvey.org, for real-person complaints and experiences with a variety of vehicles.
Here are all CarGurus' Kia Optima reviews: http://www.cargurus.com/Cars/Reviews-d158-r6186-Kia-Optima.html. Sounds like owners have had issues with build quality & electrical issues.
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