I am not sure a shed or building your own would be a good start for someone only wants to get started with a couple of chickens, in a backyard setting, to see if they like it.
We are all assuming they will like it because we all do!! But let’s be honest, chickens aren’t for everyone or everyone would be doing it!
Here is my 1 cent (I lost the other sense a long time ago!)…
– Working with wood, saws, and building things is intimidating to someone who has never done it and doesn’t have anyone to show them how. So I don’t recommend jumping into a build on your own unless you are prepared
– Plastic has some big advantages such as ease of cleaning, lightweight, etc. The big downside, it’s a lot more difficult to improve or add on to later, and once it deteriorates it’s toast.
– If you cannot cut wood, have no tools, and no means to get wood home. I do not recommend building a coop, even a small one. It’s not as easy as youtube makes it out to be!
– What you posted would work to get started in my opinion. You would want to make sure to predator proof it, so nothing could lift it, etc.
– For 3 birds, most of the large (or xlarge) prefab coops will work. You will be maxing them out though, even if the prefab coop says it holds 6 or 10, it will only really hold 3-4. The advantage to a prefab coop is, it’s delivered in a box with all wood pre-cut, all parts there, directions included. Most grade schoolers can put one together (I can attest that I completed one without much issue!). The downside is the cost, they can be hit or miss on quality (seems like a lot of miss), and if you want to expand your flock, you can’t without building another, expanding that one, or putting in a lot of work one way or another.
– Doghouse + dog run enclosure + bird netting (the same thing as the links you’ve posted) = likely the cheapest, easiest option. Seems like people are always giving away dog houses for free.
– I believe the best option, a lot of times, is to build your own or turn a shed into a coop, but in this case I’m not convinced.
If you look around here at coop pics you will see everything from the nicest Chick Majal to the ghetto-fabulous-est of conglomerations. In they end, the need to be dry, draft free, and safe from predators, that’s what matters
Good luck, keep us updated on your progress!