speculators are snapping up bargains in Scotland's luxury property market as one in four of homes worth £1 million and more sold this year were bought by investors from outside the country.

Savills estate agent said the good value offered by the prime housing market in comparison to the rest of the UK, especially London, was luring overseas buyers, particularly from Hong Kong, China, Russia and Canada.

They are tending to concentrate their interest on Edinburgh, Argyll and Aberdeenshire.

There has also been increased interest from the Scottish diaspora in places such as Australia, where favourable exchange rates allow investors to trade in their local currency for high returns in sterling.

Figures for the whole of the Scottish property market, compiled by Savills and presented in Glasgow yesterday, reveal that 25% of all properties sold for £1m or more in the first six months of this year were snapped up by non-Scottish residents, up 9% on last year's figure.

The bulk (17%) came from overseas, with the remainder made up of 2% of buyers from London and 6% from the rest of the UK, excluding the capital.

Andrew Perratt, head of Savills residential property in Scotland, said: "Prior to the downturn, many Scottish sales at the top end of the market were generated by local entrepreneurs and financiers. This set of buyers has fallen away in recent years, and the Scottish market is increasingly relying on those from further afield."

Mr Perratt added that buyers were attracted to the good property deals available in Scotland.

"Scotland is astonishing value for money," he said. "You can buy a flat in the west end of Glasgow for the same price it would cost to rent a flat in Mayfair for a year. So you can get a two-bedroom flat in the west end for £200,000 or you can spend £200,000 to rent a two-bedroom flat in Mayfair for the year.

"Likewise, you can buy a one-bedroom flat in London's One Hyde Park – the most expensive development in the world – for £6.5m, whereas we currently have the Isle of Shuna in Argyll, an entire island off the west coast of Scotland, on sale for £1.85m."

Savills, which mainly handles properties worth upwards of £400,000, also said uncertainty surrounding the outcome of the independence referendum is making homeowners in Scotland's prime property market reluctant to sell.

It said its agents were increasingly being asked by clients whether an independent Scotland would increase or decrease the value of their homes and whether they should wait until after the 2014 referendum before marketing their property.

The estate agent added that while it felt the question of independence was not putting off overseas buyers, the full impact of the uncertainty surrounding the referendum had not yet filtered through the market.

Overall, Scotland's million-pound property market remains far below its peak of 289 sales in 2007. By last year sales had fallen to 139 and look like dropping again this year, with 48 sales in the first six months of this year.

l A Scottish Government scheme that helps people get on the housing ladder is being opened up to all first-time buyers after funding for it was doubled.

The budget for the open market shared equity scheme has been increased from around £10m to around £20m.