A report from international mortgage specialist Offshoreonline.org showed buyers could gain as 12% by researching locations more carefully. Its conclusions were based on data from the UK Land Registry.

Many expat investors look at average figures across regions or cities when buying real estate, when in fact prices may vary significantly across individual neighborhoods. In London, for example, prices in Islington have risen 8.5% over the past 12 months, while those in Bexley have fallen 3.4%.

Said Erica Evans of expat search consultancy Expatfindaproperty.com:

All too often average data hides a far more complex picture, and for overseas buyers in particular, who may not have a detailed borough by borough knowledge of the Capital, buying can be fraught with difficulties. We regularly receive enquiries from buyers looking to establish a foothold in London, but many will end up changing their mind as to where they wish to invest once we have shown them the true local picture.

Evans added that traditional quality areas might appeal to flexible investors. Areas such as Wandsworth, Kensington and Hammersmith offer a selection of properties across price ranges. They also feature sound retail, transport and community infrastructure, she said.