How do you post a customer prepay?

You can record it as a retainer, r-vinson.

This is a payment treated as a liability. Then, when you invoice the customer and receive payment against it, you'll turn that liability into income.

We'll set up a liability account first. Please follow these steps:

1. Go to the Gear icon, then select Chart of Accounts.

2. Click the New button. From the Account Type drop-down menu, select Other Current Liabilities.
3. From the Detail Type drop-down menu, Client Trust Accounts - Liabilities.
4. Enter a name for the account and select Save and close.

The next thing we need to do is to create a retainer item that we can use to record the payment.

1. From the Gear icon, select Products and Services.
2. Click New and select Service.
3. Enter a name. From the Income account drop-down, select the liability account you created.
4. Select Save and close.

Once done, you can create a Sales Receipt or Invoice for deposits or retainers. Please check this link and proceed to Step 4: Record a retainer or deposit.

Keep your posts coming if you need more help. Stay safe!