How to Record Projected & Actual invoices

Hello,

I'm trying to figure out how to record these invoices that I have that involve both a projected amount and how to record the actual amount for our purchase of service. 

The projected amount we pay using estimated data so the break down would be something like.

Covid Hazard Pay - xx, xxx

Purchase of Service - xxx,xxx (using state funds)

Total = 316,709.65

That's pretty simple but then we get our actual data that has the breakdown of info that we need to show in our expenses

Purcase of service - xxx,xxx

Covid expenses - xxx.xx

Receivables (xxxx.xx) (these get deducted from vendor)

Total = 315,548.31

We have a remaining balance due of $1,161.34

Does anyone know how this would get recorded? We obviously cut the check for the projected amount, but then we receive the actual data and is confusing as to how to record the expenses such as the actual purchase service amount, our covid expenses, etc. I always end up with an negative number in my bill and have to figure out where to take it out from and record the credit and has messed up our purchase of service line in the P&L.

Any assistance would be appreciated.