HELP with modifying part of existing storage bldg. to hen house!!!

I have five 2 week old pullets for which I am attempting to set up house. There's already a "dog run" that will make a great chicken run and keep my dogs away from the chickens...the hens will have access to this during the day. For night time security I want to turn 1/3 of my storage building into a hen house. I want to utilize the right of the doors (which i've removed to do the work). I'm struggling with a floor plan. This was a work bench area for the previous owner but I just need ideas in terms of how to modify it for hens/easy cleanup. I know where I want to put the nesting box and that I'm going to add ventilation, but everything else is up in the air. I have lots of materials to work with, I just want easy access to everything for cleaning from inside the storage building. Pics below...thanks in advance...I'd love to get this project done tomorrow!