All our returning customers have 5% discount

Ordering software with total cost (without delivery cost) less than $200 - no discount (or %5 if you are returning customer)

Ordering software with total cost (without delivery cost) from $200 to $300 - %5 discount (or %10 if you are returning customer)

Ordering software with total cost (without delivery cost) from $300 to $400 - %10 discount (or %15 if you are returning customer)

Ordering software with total cost (without delivery cost) more than $400 - %15 discount (or %20 if you are returning customer)