OrderLinePriceTier

One tier of graduated or volume pricing.

flatAmount
Type: number

A flat fee for reaching this tier. In minor units (cents for USD).
lowerBound
Type: number

The tier's first unit.
tierBillingType
Type: "perUnit" or "flat"enum

flat charges only flatAmount; perUnit charges unitAmount per unit plus any flatAmount.
unitAmount
Type: number

Price per unit in this tier. In minor units (cents for USD).
upperBound
Type: number | null

The tier's last unit; null or absent on the last tier.
propertyName
additionalPropertyType: anything