Hello and welcome to the QuickBooks Community, jrfarrow. I see you are having some issues with your A/R and balance sheet in one of your business files
Making changes to the amount you paid for the inventory should not directly affect your Accounts Receivable balance. The A/R account tracks outstanding sales transactions, not payments made when the item was bought.
Instead, the A/R account would also be impacted if you changed the details on the actual sales transactions.
Given that the invoice is showing $10,500 for a single item, I would also expect your A/R balance to match that full $10,500 amount, assuming no credits or advance payments were applied.
The fact that your A/R shows only $5,000 likely indicates some type of data corruption or damage has occurred in your QuickBooks Desktop company file.
Here are a couple of articles that can help you troubleshoot and resolve possible data issues:
After that, go back to the balance sheet report and check if everything is now correct.
Let me know if you have any other questions as you work through the troubleshooting steps, jrfarrow. You can also post new questions if you need anything else. I'd be happy to provide assistance and articles to guide you through.