Dear sifu, need your advise about car insurance price calculation.

My Car - Myvi (2008) SXI.

This insurance company quote me RM 275.00 after deduct 55% NCB for Sum insured RM 21,000.00.
I feel that they charged me too high due to value of my car only RM 17,000.00.

Then i asked them to quote me for sum insured RM 18,000.00 (lowest they can offer).
But after recalculated & they quote me RM 271.00 which only cheeper by RM 4.00.

With RM 3k reduce only cheeper by RM 4 only?

Kindly advice.

Just need to know how they calculate the insurance premium with more detail.

I used some website calculator tool where result also different from what they quoted me.