Let me share with you the process, Jbell.

When you create the purchase order, you'll have to enter a quantity and amount. This way, you can create a partial bill. In your case, you'll have to add 6 as the quantity and 12,500 as the rate. It will total to an amount of $75,000. 

Then, create a bill from the purchase order. We'll have to change the quantity manually to 1. This way, it will only convert $12,500. I know you want it to show $12,000. However, if we enter the amount $75,000 without adding any quantity and rate, you're unable to convert the purchase order partially. 

Once done, you can check the purchase order. It should show 1 in the RCV'D column. It means you've created or converted 1 bill from it.

I'll add this reference to help you manage your purchase orders: Create purchase orders in QuickBooks Desktop.

Feel free to click the Reply button below if you need more of our help. We'll get back to this thread as soon as we can.