Refund wanted on Rio

We bought two Kia Rios in March this year for what we told was the best price possible. A month later I noticed a blemish in the paintwork on the roof of one of them and contacted the dealer who got approval from Kia to fix the roof. The rectification has been done.

I then contacted the dealer to request a refund for the damaged vehicle. They said no, so too did Kia. I believe that I have a sub-standard paint damaged vehicle which was also used as a demonstration vehicle at the local shopping centre, therefore a vehicle which has a lower price than the so called best price I was offered. I now find that Kia is offering these vehicles at a much reduced price. Do you believe I am due a refund from Kia, alternatively they could fit extras to our both vehicles to compensate us for the paint problems, such as cruise control to both vehicles and side window shields. Am I being unreasonable?