How do I attach multiple payments to a single invoice?

We are pleased you have joined the Community, lamottelectric. Allow me to explain the process for applying multiple payments to one invoice. 

If the small payments were recorded manually, you can match them through the Receive Payment window. Here's how: 

1. Open the invoice and click Receive payment. 
2. Scroll-down to the Credits section.
3. Select all payments that you want to attach.
4. Click Save and close.

Regarding your inquiry about down payments, I am happy to inform you that this feature is already available in QBO. 

I can also guide you through the steps to enable it. 

First, follow these steps on how to set it up:

1. Go to Gear or Settings icon ⚙ and select Account and settings.
2. Proceed to the Sales tab.
3. In the Sales form content section, select Edit ✎.
4. Look for Deposit and slide the bar to the right to turn it on.
5. Click Save, then select Done.

Once activated, a Deposit field will show up just below the Total amount when creating an invoice. Here's how:

1. Click the + New button and select Invoice.
2. Put in all the details of the invoices.
3. Enter the 50% amount of the total balance in the Deposit field.
4. Click Save and close.

For more details on setting up and using deposits on QuickBooks Online invoices, please refer to this helpful article: Add a Deposit to an Invoice in QuickBooks Online.

In addition, here are some other helpful articles about working with deposits and partial payments in QuickBooks Online: 

• Link a Bank Deposit to an invoice in QuickBooks Online
• Record and Make Bank Deposits in QuickBooks Online

Please inform me if you have any further inquiries regarding the matching of payments and the utilization of deposits on invoices, lamottelectric. I aim to provide you with all the necessary information to effectively utilize this feature.