Unfair mismatched pricing

I had a 2015 Toyota Corolla top of the range [1.8 exclusive CVT] insured with Outsurance approx 45 000kms on the clock for an amount of R766. On Thursday last week I called to replace the Toyota with another vehicle which is a 2013 Kia Picanto 1200 - the cover on the Kia is R771. All other factors are the same with regards to excess etc. I cannot understand howcome this is higher considering that the value of the Kia is more than half that of the corolla as well as that it's an older vehicle. I indicated to the agent that I am totally dissatisfied with the rate. Please contact me with a review.