Why not just make another Google Account just for this project?
It’s what I do since year, basically for every customer I work, I create a new account and even share the credentials with the customer (if he wants it).
It’s what I do since year, basically for every customer I work, I create a new account and even share the credentials with the customer (if he wants it).
Same with Amazon accounts and AWS bills for that matter.
I understand the concern though... and using separate accounts is probably best practice.