Reconcile a spreadsheet of 3500 items

I have an spreadsheet of our account receivables that require reconciling. We have charges and payments coming in from tenants that need to be matched up. If the charges match up (which can be identified with matching names, I would like the items to be highlighted green. If there is a payment or invoice without a correspondening item in the same month or a few days later, I would like the item to be highlighted orange. If you see something that does not have a matching item at all, I would like those items to be highlighted red.