Micro homes are certainly a growing phenomenon. New, innovative concepts are popping up everywhere... but the US. What lessons can be learned about the product, the demand and the financing from the countries that are ahead on this trend?

David Blake, principal mortgage adviser at Which? Mortgage Advisers, said: "With the average London micro-property selling for £279,000, smaller homes can represent a more realistic opportunity for many - but can also be harder to mortgage."

Which? found that Nationwide and RBS would not lend on properties with floor areas smaller than 30 sq m.

Mr Blake said: "Smaller properties can put lenders off due to concerns around the future value of the investment. However, there are mortgage lenders who are receptive to properties of this nature, if demand is high enough and sustainable."

Properties smaller than 37 sq m rose in value by 6.9% in the last three years, compared with 8.7% for homes larger than that, Which? found.

'Find the space'About 7,800 micro-homes were built last year, up from 5,605 in 2015, helped by changes introduced in 2013 that allowed developers to convert city centre office blocks into flats.

Two thirds of the properties Which? looked at were in London - including Barnet House, which offers flats as small as 16 sq m.

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