Nah, not possible. In fact, since a while ago it’s not even possible to have different credit cards for different accounts created using the same Google account as they are automatically linked to that accounts Google Payments profile.
(And yup, that’s extremely bad if you set up a clients Ads account with your profile since suddenly one of your clients may pay for the other clients campaigns and you can have only one billing address. I actually brought that up with someone who works at Google at the Ads department and they told me this is a “niche case” because naturally clients always set up their own accounts lol)
**What you gotta do now is the following:**
1: Use (or create) a separate Google Account for each campaign you want to bill separately.
2: Set up a separate Google Ads account for each campaign.
3: Be careful to not add any other admins until you create a new Google Payments profile by adding a unique credit card for each account.
4: Add the admin from which you’ll manage these campaigns or set up the MCC.
5: Verify by going to [Google Payments](https://payments.google.com/gp/w/u/0/home/paymentmethods) that there’s a separate profile for each account with a campaign that’s supposed to be paid separately and each one has their own, unique credit card.
6: If something goes wrong, you’ll need to reach out to Google support because, once a Google Ads account is linked with a Google Payments profile you can’t disconnect it. Only Google can. You can also start praying in that case (optional)