In its services and repair terms and conditions, Google says it will keep devices sent in for repair if they have a non-OEM part.
Update:
Google changes repair policy after criticism of third-party parts ban Google previously said it would not return mailed-in devices using “unauthorized” parts.
If you send in a phone with non-OEM parts it’s safe to assume that it’s a bit on the older side. You’re probably sending it in instead of buying a new phone because you can’t find a repair shop that will work on your device because sourcing parts can be difficult for older devices. If you’re suddenly hit with a bill that costs more than the value of a new phone, or at least a replacement, suddenly paying becomes questionable. But yeah, you’re right. It feels like theft.
Okay but there is a thing called Estimate and either the customer agrees with the bill or they need to give the item back.