Hello @krystajfox,

As of the moment, there isn't an integrated way of customizing your report and compare your accounts receivable balances per week. You're on the right track in exporting your Accounts Receivable report per week and combining them via MS Excel file.

Lastly, here's a few articles you can read to help manage your account and related transactions: Help Articles for QuickBooks Online.

If there's anything else that I can help you with, let me know in the comments. I'll be here to lend a hand.