My company pays for transportation of the car. Should I buy the new car at Missouri or California? Thanks!

Welcome to the AF!

Check CA laws about out-of-state cars needing to pass emissions requirements. You may have trouble registering your car if they have tough requirements for registering cars from out-of-state. In that case, you better buy a CA Prius.

Update - You are probably better off buying the car in MO since they are probably alot cheaper than in CA.

http://www.arb.ca.gov/msprog/NonCAVeh/NonCAVeh.pdf