Most instruments and supplies have more than one manufacturer and model. The specific brand to be used depends on cost, on the preference of laboratory and medical personnel, on the location of the manufacturer, and on the availability of after-sales training and service. A detailed comparison of different equipment manufacturers, suppliers and price quotes needs to be conducted before any equipment is purchased for the laboratory. Other factors that need to be considered when purchasing new equipment include payment method, price of consumables, technician support, service warranty and service contract cost after the first year. Large and sensitive machines or equipment should be delivered to the clinic by the manufacturers or their agents, and should be installed without additional cost.