"Spot Buy" button is available on any individual part's page, as seen on the right side of the screen below. Clicking this button initiates a part sourcing workflow, which allows you purchase parts from suppliers, or request Cofactr to send a request for quote (RFQ).
Clicking the "Request Quote" button will trigger Cofactr to acquire a specific number of parts on your behalf. A Cofactr dialogue will pop up to gather a bit more information:
Cofactr will ask you to enter a part Quantity. This is the number of parts you are looking to purchase. As soon as you submit the form, Cofactr will search across all distributors, considering their parts price, shipping, and any potential customs costs, and produce the best price possible on the parts at various lead times.