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I looked at that coop. It's *marginally* better than some prefabs, but it's measured in inches when you need feet.
It's also badly deficient in ventilation, which is critical for us residents of the Steamy Southeast. (If you put your general location into your profile it will help people give better-targeted advice). For us, an Open Air coop is an excellent option, well-suited to our climate.
Here are the numbers for you:
The Usual Guidelines
For each adult, standard-sized hen you need:
- 4 square feet in the coop (.37 square meters)
- 10 square feet in the run (.93 square meters),
- 1 linear foot of roost (.3 meters),
- 1/4 of a nest box,
- And 1 square foot (.09 square meters) of permanent, 24/7/365 ventilation, preferably located over the birds' heads when they're sitting on the roost.
4 hens
- 16 square feet in the coop. 4'x4' is the only really practical build for this given the common dimensions of lumber.
- 4 feet of roost
- 40 square feet in the run. 4'x10' or 5'x8'. 6'x6' is a bit too small, 6'x8' is more generous and easier to build than 5'x8'.
- 4 square feet of ventilation. A 2'x2' window is theoretically enough, but in practice doesn't create any air FLOW so better to spread the venting around (and even better to exceed the minimums, especially in warm climates).
- 2 nest boxes, to give the hens a choice
This is a coop designed specifically to meet the needs of 4 hens:
https://www.backyardchickens.com/articles/the-little-monitor-coop.76275/
I suggest that you plan plenty of run space because, due to their crests impeding their eyesight, they don't forage well and are not predator-alert.
Do you or any friends/family members have any handyman skills at all? The coop I linked, with it's Monitor Roof, would be complex for a beginner, but a simple shed style coop is a good first project.
Alternately, converting an appropriate-sized shed is almost always a better use of money than buying a pre-fab, which will also need a lot of work because you'll have to open up a LOT of ventilation, replace the worthless door latches with something predator-proof, reinforce the structure over time, and generally keep fussing at it as parts fail.
The easiest build for a complete amateur -- and an option well-suited for our climate, is a hoop coop.
This is a particularly good one, though 1/2" hardware cloth is a better option than the chicken wire because dogs and raccoons go right through chicken wire.
https://www.backyardchickens.com/articles/the-biddie-bordello-a-hoop-coop-run-combo.72189/
This is another good one:
https://www.backyardchickens.com/articles/permanent-hoop-coop-guide.47818/
Some hoop coops skip the wooden frame at the bottom and just use 4 U-posts to secure the cattle/hog panel.
https://www.backyardchickens.com/posts/23607034/