Hello,
Matt here from the Guru Team! :-)
That is a great question. While Shopify stores were not built to include this feature directly I did some digging and found an app that sounds like the closest fit to what you would like to do. :-) It is called Trade Orders and can be found here. As explained with in the description it "can be used for payment on account, trade orders or for any situation where you want to allow a certain group of customers to complete an order without taking financial paymentupfront". You are in luck as it comes with a free 7 day trial as well so you can try it out and see if it is a good fit!
I hope this helps and you have a great day,
Matt