Enum describing possible payment modes.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v25/enums/payment_mode.proto)

| Enums ||
|---|---|
| ## `CLICKS` | Pay per interaction. |
| ## `CONVERSIONS` | Pay per conversion. This mode is only supported by campaigns with AdvertisingChannelType.DISPLAY (excluding AdvertisingChannelSubType.DISPLAY_GMAIL), BiddingStrategyType.TARGET_CPA, and BudgetType.FIXED_CPA. The customer must also be eligible for this mode. See Customer.eligibility_failure_reasons for details. |
| ## `CONVERSION_VALUE` | Pay per conversion value. This mode is only supported by campaigns with AdvertisingChannelType.HOTEL, BiddingStrategyType.COMMISSION, and BudgetType.STANDARD. |
| ## `GUEST_STAY` | Pay per guest stay value. This mode is only supported by campaigns with AdvertisingChannelType.HOTEL, BiddingStrategyType.COMMISSION, and BudgetType.STANDARD. |
| ## `UNKNOWN` | Used for return value only. Represents value unknown in this version. |
| ## `UNSPECIFIED` | Not specified. |