You can only add one contact information to your customer profile, crosey97.
In QuickBooks Solopreneur, you can add only one customer profile to a specific client. With this, you can create two customer profiles and write specific details in the Notes column for your client regarding orders and billing.



If you wish to add a sub-customer in QuickBooks, consider upgrading your subscription to QuickBooks Online. This way, you can avoid the need to create two customer profiles. To determine the most suitable version for your business, you can review this article: Upgrade or downgrade your product's edition.
Additionally, I'll share this article as a reference for recording customer payments in QuickBooks: Record invoice payments.
If you require further assistance, don’t hesitate to leave a comment below. I’m here to help.