Choosing a vendor can be as simple as asking friends who they use for their business. Other, I would take certain steps to choose right vendor such as document my organization needs, identify the sources- do my own research, measuring supply performance, and communicate with different vendors and see how well they satisfy end-user. Other things, I would look for flexibility, time delivery, customer service. Important part of selecting a vendor to make sure that the discounts on the price list are always negotiable.