Dubbed "Scotland in miniature", Arran would seem to contain all that we most like to celebrate about the nation as a whole – from the granite heights of Goat Fell to the island's sandy beaches by way of its history, wildlife, golfing and whisky.

But to that tourist-friendly list of attractions need to be added other, less desirable features. They include a chronic shortage of affordable homes, a problem that Arran shares with the rest of the country and which is a contributing factor to homelessness in rural and urban communities right across Scotland.

That's the reason why Scottish Churches Housing Action – also known as Churches Housing – has formed a partnership of charities in a development scheme which it claims is unique.

The partnership aims to acquire empty properties on the open market, which can be rented out to those who most need them at rates they can afford. Called Whitebeam Homes, the new company takes its name from a rare tree endemic to Arran, but the idea is one that those involved believe could make its mark throughout Scotland.

Homelessness is not immediately obvious on Arran. You're unlikely to be met by poorly-dressed men or women asking for some loose change as you step off the ferry in Brodick. But that isn't what homelessness looks like for most people, says Alastair Cameron, chief executive of Churches Housing. "If a 40-year-old man is living with his mum because he has no other options, that is potentially a homelessness situation. He's got no enforceable right to be there if the relationships go wrong."

When families or individuals resort to living with relatives or packing into a caravan, Alastair says, homelessness becomes a hidden problem too easily forgotten.

Efforts by the Scottish Government and local authorities have led to an encouraging decrease in official homelessness figures over recent years, but there aren't nearly enough houses to go around.

On Arran, the problem is exacerbated by the number of properties bought up by visitors sufficiently enamoured with the island's beauty to buy a holiday home there. John Inglis, chairman of Arran Community Council, lives in Sannox in the north- east of the island. "In 12 years, no house in Sannox sold has been bought by a local until three months ago," he says. Across the whole island, this trend has pushed house prices and rents far beyond the reach of many local residents, effectively shutting the door on their chances of getting a foot in the housing doorway.

Mr Inglis says the proportion of households on the housing list for Arran (currently 5% of households) is double the percentage there was on Mull some years ago – "and Argyll and Bute authority considered that figure a scandal even then".

He welcomes the notion of a new, private landlord like Whitebeam, prepared to establish an allocation policy that focuses on families and individuals who can't afford private rents but won't score high points for social housing.

"Housing associations go to great lengths to build new, affordable homes but it's a tortuous process and takes years," Mr Cameron says. Moreover, though North Ayrshire Council is currently working with Irvine Housing Association to construct 56 new homes on Arran, locals say that such social housing estates not only fail to maintain the character of existing villages but have an unavoidable stigma attached to them.

So when the United Reformed Church decided to sell its redundant church building in Sannox, it soon became clear that an alternative way forward was presenting itself.

The church denomination has a policy of prioritising the option of creating affordable housing whenever it sells a church building. The Rev Leslie Morrison believes churches have a moral obligation to support local communities.

So his denomination has joined forces with Churches Housing and used the proceeds from the Sannox sale to fund Whitebeam Housing's initial goal of buying two or three houses that can be rented back to local residents at less than the current market rates.

With the second home market in the doldrums, in Arran and elsewhere, the hope is that this initiative could offer a wider model, for more investment in bringing empty properties back into use. This could avoid the problems faced by many housing associations which are struggling to achieve the finance needed for major newbuild projects.

In the case of the Sannox sale, the scheme has been supported by community and transport planning expert George Hazel. He is behind the purchase of the Sannox church, with a view to establishing it as a Christian retreat. He has now become a third partner in the Whitebeam initiative.

By buying existing homes within villages, Mr Hazel says, Whitebeam can begin to house those on low incomes in a way that doesn't mark them as in need of social housing while helping to repopulate villages that have suffered economically from so many homes remaining empty for much of the year.

It's a good time to undertake such an initiative, adds Mr Cameron. In the current climate, many second-home owners have put their Arran properties back up for sale in the past few years but are struggling to sell. He and Mr Hazel hope that others will come forward to help fund an enterprise with a clear social and ethical appeal.

Mr Morrison says the model appeals to politicians and has already attracted interest from as far afield as Aberdeenshire. "It's about the third sector taking the initiative, putting in new money and attracting funding from private investors and philanthropists."