Welcome to the QuickBooks Community, @cha0531. Let me guide you on how to put a disclosure note on your invoices. 

Providing a disclosure note to our customer as a guide is great. These can help the customer understand the limitations of what we can change for them.

Just follow these steps to create the note: 

1. Go to the Gear icon. 
2. Select Account and Settings.
3. Go to Sales.
4. Scroll down until you find Messages, and click the Pencil icon.
5. Provide the disclosure note, and click Save.

Another way to create a note is: 

1. Go to the Gear icon.
2. Select Custom form styles.
3. Select Edit, under Content.
4. Select the lower part of the PDF.
5. Provide the note, and Select Done. 

I wanted to share this article with you for your reference regarding your invoice: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Moreover, let me share these articles that can help you manage your invoices in the future: 

• Record invoice payments in QuickBooks Online
• Send invoice reminders automatically or manually in QuickBooks Online

If you still have questions, feel free to reply on the thread or create a new post. Have a great one, and take care!