There are two plates in the Engine bay for the Kia Classic. One is for the Chassis and Engine numbers. The other is for the CNG Cylinders serial numbers (if your car has FF CNG installed).
As for the chassis condition, your friend prolly wanted you to check the underbelly to see if there were any touch-ups, bumps, dents, rust, or any weird looking stuff there. Its not that hard to notice and even the guy at the service center can identify whether the underbellyis A-OK or not.