I am currently looking into a solution which will allow me to issue credit card/debt card to a set of workers for my startup, so they can purchase items on users' behalf.
I did a bit research how instacart or postmates work, it seems they issue a prepaid visa cards to their courier. http://www.quora.com/How-do-Instacart-and-Postmates-shoppers-pay-for-items-ordered-by-the-customers
Have anyone done this kind of thing before? Would love to hear how you handled it and share your experience.