I was going to post the links that Chickkat posted. I used those for inspiration. I am really new to chickens, and needed something to be discrete in my backyard for a small (3 hen) flock. My husband said it had to be cheap (of course it ended up costing twice what I had planned). I got a dog house off of craigslist similar to yours. We tried to flip the top part around, but water immediately got in (we were setting this all up during T.S. Lee which didn't hit us, but came close enough to rain down on us). So we have the dog house set up with pine shavings and have a divider to make the back part into a nest box. We put the dog house on pavers inside of a dog kennel that is 4 feet high that we bought off of craigslist. The ad said it was only 6ft by 4ft but I am pretty sure it is bigger based on the amount of hardware cloth we have used to reinforce it (a 4ft high 25 foot long roll didn't make it all the way around). It is at least 6x6 and maybe even over seven feet. We put the hardware cloth up the side by 3 feet and put out a 1 foot apron. We covered the top with poultry netting (and I want to go back to add pvc pipe to form a bowed roof for more head room). It needs more work and I am already dreaming about making a real coop for more chickens. Ours is designed to be mobile though so that we can move it around the yard for more forage (the girls get out for an hour or two in the late afternoon when our dogs are locked up and we can supervise).