Australia is a bad place for first home buyers. Booming property prices, stagnant wages, and negative gearing have all created a real estate market that is virtually impossible to enter without some dramatic lifestyle sacrifices. Unless, of course, your parents can spot you $100,000 for a deposit.

But there is actually a way to own a house cheaply. And not just any house, but a tiny house, which is exactly what it sounds like but with a design modeled around environmental sustainability.

Nye and Tess Stewart are one such couple who have built a tiny house in Australia. They live just outside Brisbane in a place they built themselves on a block of bushland. Fighting their way into the city's overheated property market wasn't high on their agenda, so instead they dropped $20,000 to build their own place. And now they've done it, they think could do it again for half that price. We asked them how.

For Nye, the first step was to spend a few years reading everything he could find about sustainability and tiny houses—and there's a lot. The internet is kind of obsessed with tiny houses. The problem is that most of them gush over tiny house aesthetics while rarely getting into the nitty gritty of construction. For that, you can't go past Robert Rich's Earth Garden Building Book, which is a bible for eco-builders.

The Australian Tiny Homes Foundation is another great resource. It's a non-profit organisation that provides shelter for the homeless by building communities of tiny houses around the country. They even have tiny house plans on their website, which you can download for free.

Tiny house Facebook groups also have a lot of handy information, and can be a good place to meet others with some construction experience. Nye also recommends sources like Tiny Texas Houses (the project of an American environmentalist who builds houses out of salvaged and recycled materials), Richard Olsen's book Handmade Houses: A Century of Earth-Friendly Home Design, DIY log-cabin builder Noah Bradley's Handmade Houses site, and Facebook group Living Off The Grid.

"The info is getting better and better," Nye says. "We're also hoping to organise some workshop days and info sessions near Brisbane soon, to share ideas and knowledge." The workshops will run along similar lines to the Tiny Homes Foundation. Punters will pay a small fee to learn how to make their own tiny homes, and the finished places will be used as temporary accommodation for the homeless.

Nye and Tess Stewart bought their own block of land just outside Brisbane—but if you can't afford your own site, there are alternatives. "There are loads of communal living groups around," Nye says, "and websites where you can source somewhere cheap to use as a plot of land."

Check out the Cohousing Australia Initiative, which helps people to organise and promote their own rural or urban co-living communities, or the Willing Workers On Organic Farms program (WWOOF.com.au). This is where owners of organic farms often donate farm space for workers to live on, in exchange for their help around the farm. You can also find cheap land advertised on Gumtree's Land For Sale page—two kilometre square blocks in rural NSW or Victoria will set you back between $6,000 and $10,000.

Unfortunately in Australia it's illegal to live full time in temporary accommodation, like a caravan or a tiny house on a trailer. But if your tiny home is anchored to the ground with a permanent foundation, you won't have any council troubles (you can find out more about different types of permanent foundations at website The Tiny House).

Nye and Tess built their tiny house by hand in the backyard of their old rental place, working off design tips in resources like the Earth Garden Building Book. They went with an open plan design with three separate rooms—a main living area and two side rooms that can be folded into the centre, so the whole house can be packed up and transported on the back of a trailer. The finished structure is about six metres wide by six metres deep. But in that small space they've packed in everything they need—including an indoor hot water shower and composting toilet.

"The centre section has all the plumbing, electricity and solid fixtures, including the kitchen and bathroom, with a loft bed above," Nye says. "The two wings or side sections are open plan for a lounge area, extra bedroom, storage and sitting areas, and I've also built a small deck on the front.

"All up, we've got two double beds, a lounge area with 12 volt TV and bean bags, composting toilet, shower, kitchen area with sink and bench space, 12-volt normal sized household fridge-freezer, storage shelves and a sitting area for eating and working."

The beauty of building your own tiny house, Nye says, is that the design "can be adapted to anyone's needs. The more comforts you want, the more you need to spend, like any house… But if you want the McMansion with a giant refrigerator, heated Olympic swimming pool, and air-con in every room, perhaps this is not for you."

Nye and Tess Stewart spent just under $20,000 on their tiny home, but say they "could build it for much less now knowing how to go about it, probably closer to $10,000… and if you're willing to scratch around for free and recycled materials you could do it cheaper still."

The biggest expense was their solar energy system, which came in at $3,000 all up for six 250 watt solar panels that feed power into deep cycle gel batteries. The whole system is operated by a 40-amp MPPT (Maximum Power Point Tracking) charge controller installed in the main room, where they can keep track of their power levels.

Nye bought his solar panels off eBay, but reckons it's useful "to talk to professional solar energy companies about your options—these guys know their stuff and are usually very happy to talk solar and help you out. As far as I can tell the cheap solar panels work just as well as the expensive ones, and there are plenty of good second hand ones around." Again, he suggests hunting around eBay or Gumtree for options.

Besides the $1,200 they invested in a low energy fridge, the other major cost was a "fancy composting toilet" for $1,300—but Nye says it was worth every cent as it eliminates the stench of your typical camping ground long-drop. The toilet works by separating the urine from the solids using a special seat, while a bucket of biodegradable material like sawdust or grass clippings is on hand to cover the waste and kill any odours.

"The dry stuff breaks down very effectively," Nye says, "and can eventually be used as a safe compost on non-edible gardens. You have to "deal with your waste" every couple of months by storing it outside in containers, but it's really not that bad. A 12-volt fan draws air from the chamber up a pipe and through the roof, which helps to break things down and remove smells. It actually smells less than an ordinary toilet, if you can believe it. And if your budget's tight, you can build one yourself much more cheaply," Nye says—you'll find designs at sites like Permaculture News.

As for the house structure itself, Nye and Tess went fully DIY with little more than "a pair of variable speed cordless drills, a good quality hand saw, a couple of G-Clamps, and some trousers with lots of pockets."

They used recycled hardwood timber for the frame, plantation pine for the walls and plywood for the floor, which is "very forgiving and super strong," Nye says. The roof is made of lightweight polycarbonate sheets, with marine plywood for the exterior cladding and thin ply for the internal cladding—they're all materials you can buy at supply stores like Bunnings. They even made the windows themselves from tinted perspex. "It's awesome stuff," Nye says. "You can cut it to size with a saw and drill and screw it to a frame. It's very forgiving and much more resistant to movement and shock than glass, if you're moving your home around."

Nye and Tess also did all the plumbing and electrical wiring themselves after asking advice from professionals and researching on the internet—but they recommend hiring professionals if you're not confident in your tradie skills.

"The most important thing is to be safe, and it's best if you're on the tools to have the mobile phone close and not to work alone if you can," Nye says. "If you're having an off or clumsy day, do something else and try again tomorrow."

Their plumbing uses the same kind of 12-volt pump you'll find in boats and caravans (you can buy them on eBay), connected to a tank that collects rainwater from the gutters on the roof, and their hot water comes from a professional grade instantaneous hot water system, which heats the water as you need it. "The water heater's one area where you don't want to skimp," Nye says.

Between the rainwater tank, composting toilet and solar panels, Nye and Tess's bush home is nearly entirely self-sustaining. "We still do our groceries at the shop so we're not yet growing all our own food, just some herbs and vegetables at this stage," Nye says. "We also do a load to the tip every now and again with some household waste, and our hot water and cooking is provided by 9kg gas bottles which we swap over every three months or so at the hardware store. So no bills, which is very nice."

Besides moving into a small space, you'll also need to be prepared to live within your means, as far as power and water goes. "Unless you have an enormous solar energy system you have to say goodbye to high energy items like the toaster, hair straightener, iron and electric heater," Nye says.

"You might have to settle for a smaller TV and be happy to check the charge state of the batteries before trying to use large amounts of power. And you might have to get used to a different experience of going to the toilet and be prepared to plan your life a little more."

But as long as you're in an area with good signal coverage, your internet and mobile access should be fine, and for essential high energy items like power tools you can use a diesel generator, or just buy lithium ion rechargeable tools. "Air con might also be out," Nye says, "but if you design the house well and have good airflow you shouldn't need it."

"The only costs we have are the food we eat, some cleaning products and council land rates," Nye says. "Gas for cooking and hot water might be a couple of hundred bucks a year."

But of course, doing away with rent and regular bills is only a small part of the motivation for most people who get off the grid. "I feel better ethically that I know how our power is produced," Nye says. "I have a much greater feeling of self-determination, that I'm not at the whim of Big Brother and subject to the price rises of energy and other resources. I feel connected to how we live and get great satisfaction every time I have a hot shower, turn on a light or open the fridge.

"I very much enjoy watching the batteries charge on our energy monitoring screen with a cup of coffee in the morning. These things may sound silly, but all this has made me profoundly happier."

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