Presumably if you are posting here, you have a GtD system in mind. So try adapting the Workflow diagram. Suppose that the Room is the Inbox - everything has already been Collected in the Room. Next, Process each item sequentially - answer the Processing questions. Process each item before moving on to the next item. Process sequentially, e.g., start in one corner and work your way around the walls and then the interior. Organize your answers into tentative categories (trash, donate, relocate, repair and relocate, etc.) and then discuss with boss and firm up category allocations. Create Projects for items requiring repair or specialist movers.
Project: My new Office is beautiful.
Next Action: Process each item GtD-style.
Good luck. If this works, I have a a garage......