I can see how you want to record these overpayments accurately. I'm here to help you with how you can handle this scenario and be able to answer all your questions according to how it is shown below, R.K.

Transactions will appear as unapplied cash payments when funds have been received but not yet allocated to any specific sales forms. 

In QuickBooks Online, overpayments are recorded as credits in the Accounts Receivable (AR) account. To resolve your issue, create a bank account called "Clearing Account". To do so, follow the steps below: 

1. Go to the Transactions tab, and choose Chart of accounts.
2. Select New.
3. Provide the name you want or call it a " Clearing Account ". Choose Bank under the Account type field.
4. Click Save.

Once done, set up a service item like " Customer Overpayment". Here's how: 

1. Go to the Gear icon, and choose Product and services.
2. Select New and choose Service.
3. Provide the name of the product or use " Customer Overpayment " to locate it easily. Choose an income account under the Income account field.
4. Click Save and close.

Next, you'll need to record a journal entry. Follow the steps outlined below:"

1. Click + New.
2. Select Journal entry.
3. Debit A/R and select the customer. Then credit the created bank Clearing Account.
4. Click Save and close.

After that, go to the Receive payment window and select the customer's name. You should see the journal entry and the customer's overpayment listed. You can now apply the overpayment to the journal entry. See the steps below:

1. Click the + New.
2. Select Receive payment.
   
3. Click Save and close to apply the journal entry to Unapplied Payment.
    

Finally, create a credit memo and make sure to select the Customer Overpayment service item. Please know that credit memo isn't automatically created in QuickBooks.

For additional guidance on recording refunds in QBO and understanding how unapplied cash payments appear in QuickBooks, I've included these helpful articles:

• Record A customer Refund in QuickBooks Online.
• Unapplied Cash Payment Income on Your Profit and Loss

Additionally, QBO offers a variety of reports that can help you access the data you need. Just remember to apply the appropriate filters to get the relevant information for your business: Customize Reports in QuickBooks Online.

Let me know if you have any other questions about your customer overpayments. We'll always be right here to help.