Panasonic Inverter Heat Pump PCBs

[kssoin]

Hello Folks,
I had two units of Panasonic Inverter Heat Pump split unit with R410A
The outdoor unit is CU-YE18PKY and indoor unit is CS-YE18PKY.
Thee worked fine for about five year and the PCB on the outdoor unit failed. The unit were installed in 2012 . The outdoor unit PCB was locally repaired and worked for about a year and again failed. The fault codes were F99 and H11 respectively. I inquired for cost of the PCBs (indoor unit and outdoor unit) the cost of replacement is 80% of cost of new units. I am located in Delhi in India. To confirm I requested a quote from Orionair in the UK The cost was about 600 pounds.
Why are these pcbs so highly priced? Is it so with Panasonic or are other brands as expensive
what do you folks suggest I buy new units or have the PCBs replaced?
The second unit failed this year, the outdoor unit is not working, no fault code.
Regards for your time.