Help Reconciling Accounts - Formula & Conditional Formatting

Just took over a budget spreadsheet and am looking for a way to quickly reconcile one table against another. I combine the key data on to a spreadsheet and so far have been manually matching the dollar amounts with the PO #'s as confirmation of the right account. I'd like to some how get a formula into a macro that will do this for me, but honestly am looking for a better way.

In a nutshell: I need to compare to Invoice numbers and the dollar amounts that go with each. I'm thinking of a match that tells me they were matched on both criteria, but also a way to fill the cells of the ones that matched, thus making it easy for me to identify the anomalies. I put some notes in the sample and what I'm thinking it should look like, but am sure I'm making it way more complicated than it needs to be.

Thanks in advance for any help.

Anybody able to point me in the right direction?