Pricing model for a vendor service. Discriminated by model: 'cpm' (fixed CPM), 'percent_of_media' (percentage of spend with optional CPM cap), 'flat_fee' (fixed charge per reporting period), 'per_unit' (fixed price per unit of work), or 'custom' (escape hatch for models not covered by the enumerated forms — requires a description and structured metadata).
Pricing model for a vendor service. Discriminated by model: 'cpm' (fixed CPM), 'percent_of_media' (percentage of spend with optional CPM cap), 'flat_fee' (fixed charge per reporting period), 'per_unit' (fixed price per unit of work), or 'custom' (escape hatch for models not covered by the enumerated forms — requires a description and structured metadata).