Update inventory at checkout

Hello and I apologize in advance for my lack of programming understanding.  
That being said, I am trying to use litecart (v. 2.2.7)to distribute items in an educational setting that have no cost (ie. there is no charge for them).  So when I set the "in stick" at 1 item I want it removed from inventory immediately upon check out as there is o concern about the sale going through.  Currently I need to process the order to have it removed.

Any assistance that could direct me to a solution would be greatly appreciated.

Thanks in advance,
Ken

Make sure you have a payment module that sets an order status that has the property is_sale.

Then make sure the product have a sold out status set to be hidden when sold out.

That did it!
Thanks so much Tim.