His story is as much about entrepreneurship as Mongolia's economic development and real estate boom. Property prices have doubled in the past five years.

Investment money has flooded the small economy of Mongolia because of strong commodity prices and income from the sale of government licences to mine, which have resulted in increased government spending. Overseas listings of Mongolian companies have also brought money into the country.

"This has resulted in excessive amounts of liquidity in the Mongolian economy, much of which makes its way into the property market," says Cashell.

In downtown Ulan Bator, the average price for real estate is around US$1,300 per square metre, usually for an older apartment block built during the Soviet period, a fivefold increase compared with a decade ago, according to people active in this market.

The condition of these buildings is generally poor. Concrete stairwells are beaten up, plumbing is ancient, and the roofs often leak. Yet prices for older blocks have held up, largely owing to their central location.

Most Soviet-era apartments are 60 to 90 square metres, putting their prices between US$80,000 and US$120,000. Cost depends on the condition. Some have been carefully renovated in Western style, but others haven't seen a paintbrush in decades. City centre rentals for older apartments can run to US$800 to US$1,600 for a two-bedroom unit, translating into annual investment returns of 12 per cent to 16 per cent (assuming the flat is fully paid for, and there are no mortgage costs).

Focus is shifting towards higher end, modern developments in the city centre. Better quality buildings can run to over US$3,000 per square metre. For serious high rollers, the priciest accommodation in the city is Blue Sky Tower, with units selling for US$9,000 a square metre.

Most of the city's quality housing is in the Zaisan neighbourhood, four kilometres south of downtown, in a narrow valley of the Bogd Khan Mountain National Park.

Property in Zaisan starts at about US$2,000 a square metre and can run to US$4,000 or more. It's popular with families seeking fresh air and quiet.

But its location, while scenic, has a drawback: the commute through Ulan Bator's notorious traffic jams is a big hassle.

Property investors often overlook the so-called "ger" districts. These are vast shanty towns home to 700,000 people, more than half the population of the city. These suburbs of tumbledown shacks and gers lack running water, central heating, paved roads or green space.

Change may be on the way, however, as a new government has come to power on the promise of bringing infrastructure and permanent housing to these districts, opening a new market.

"Any time you have hundreds of thousands of people needing a product, there is a huge opportunity if you can figure out how to serve them," says Harris Kupperman, the chief executive of Mongolia Growth Group, a Toronto-listed property development firm based in Ulan Bator.

"Despite what most people think, people in the ger districts do have money. They are not all poor. Frequently, their land is quite valuable. They can sell that and move into an apartment. It's a question of creating a product at the right price point."

Construction is speeding up to address the shortage. Last year, 10,747 units were built in Ulan Bator, according to the National Statistics Office, compared with just 816 units built 10 years ago.

Mongolia's second-tier cities are also attracting attention, particularly those in the southern Gobi region where most of the mining takes place. Dalandzadgad, the capital of Omnogovi province, has grown in population as people move there to find mining-related jobs.

A report last year by Ulan Bator-based private equity firm Eurasia Capital says that Dalandzadgad's population will quadruple to about 60,000 by 2015 and will have the highest gross domestic product per capita among cities in Mongolia.

Just three years ago, a small street-facing shop of 60 square metres in Dalandzadgad would have cost US$20,000. This would now cost about US$70,000, according to Cashell, who bought property there.

And, unlike Ulan Bator, where many developers feel the prices are out of hand, the market in second-tier cities is just getting started.

From a legal point of view, Mongolia is an investor-friendly place. There is no limit to the amount of property one may own, although any foreigner wanting to lease land should do so with a Mongolian partner. Annual property tax is just 0.6 per cent.

The government levies a 2 per cent stamp duty on property sales and a 10 per cent tax on investment income.

The biggest risk in this market seems to be with buying property off-plan, as projects commonly see delays or are just abandoned.

And there is little legal recourse to recoup your investment if a project goes bust.

It is also risky buying property in undeveloped parts of Ulan Bator, as you'll never know what sort of building might pop up in front of the one you've just invested in. To minimise risk, buy in well-established, central areas with proven developers and cross your fingers that the boom times for Mongolia are only just beginning.