We had extra room in the garage. We built a 12x5x8 coop with a 20x5x5 run for about $250. It's 100% insulated and predator proof. Just a thought. We have 7 standard and 1 bantam, with room for 2-3 more.
We built our first coop as well and took step by step pictures if you want to take a look. It will give you an idea of the process. The link is in my sig.
All a coop is, in your country, is a box with a roost pole in it. How fancy that box is, is up to you. It can be as simply as a cube with a pole that sits with the opening down and they hop up inside to roost. A great start is a Home Depot shed or a large Craigslist dog house and simply modify it for access by you and the birds.
The biggest planning issue is whether it will be totally inside a shaded secure run (with small holed tight wire, topped and skirted) or if it will be attached to the same. If it's inside, you don't need to worry about wiring the windows or a secure pop door because the run keeps the bad guys out.