The cottage is raised about 30" off the ground on a very sturdy platform made of 2x4's and plywood. It's permanently attached to a 5'8" chicken run that is totally encased in hardware cloth. Also made of 2x4's. We painted in colored deck stain we had laying around. We call it the Aviary.
The windows, venting and door of the cottage are covered securely in hardware cloth as well - stapled inside and also screwed in.
The concerns we have with the plastic playhouse are all around draftiness and insulation in the cold weather. For the summer, this situation is going to be very well ventilated and comfortable. When it drops to below freezing we are concerned about the open air plan. We will probably install fitted plywood windows and are considering putting insulation in a can between the plastic walls. Also plan to put some weather stripping in any obvious gaps.
I didn't photograph the nesting boxes - but we installed 4 nesting boxes on the back wall of the cottage. 2-up, 2-across. It is accessible by two doors on the outside. We essentially replaced the entire side wall of the cottage with a wood inlay that supports the nesting box configuration. This is very roomy on the inside because the nesting boxes hang off the outside of the wall.
Inside the run we made a ramp that walks up to the former "hearth door" of the cottage. To create the roost, I used two wood kid's chairs that aren't in great condition for sitting on, and stuck a big wood stick through the rungs on the back of each chair. It really worked out well! We are fans of re-purposing!
We also sunk concrete edging all the way around to further deter digging predators. We think this set-up is more than adequate for 4 hens.
Some building pictures: