fiction strangeness

Writing fiction can be so frustrating at times. I may know what I want to happen, but I don't know how to make it happen. For example, right now I'm trying to figure out a scene in which my main character has to find wholesale cabinets and then install a secret compartment in one of them. My imagination is only carrying me halfway - I need to figure out where and how they will find and and install these cabinets! It can be strange inside my head sometimes!