A vending arrangement for computerized vending machines, retail displays, automated retail stores, utilizes a centralized, robotic gantry associated with companion modules for vending a plurality of selectable products. The modularized design enables deployment of half-sized or larger, full sized machines. The robotic gantry is deployed in a centralized module disposed adjacent display and inventory modules. Inventory modules can be fitted to both gantry sides, and doors can be fitted to the gantry front or rear. The gantry comprises an internal, vertically displaceable elevator utilizing a central conveyor for laterally, horizontally moving selected items from associated display and inventory positions to a vending position. Computerized software enables the display and vending functions, and controls elevator movement to dispense products from twin sides of the gantry by appropriately controlling the conveyor.