"First, I have a couple follow up questions. What size are the racks? What size is the warehouse? What is the required spacing between the racks? Are there any obstructions or is the floor totally open? After taking those dimensional restrictions into account, I would use AutoCAD to create a block representing a warehouse rack of the proper size. Then, I would use the Array command to fill the warehouse area with racking. Finally, I would go back through and delete any individual racks that interfered with columns or were in areas needed for other things, such as drive aisles or bathrooms. This method probably wouldn't be exact enough for a permanent solution, but it would give us a general idea of what the customer could expect."