Angela Rayner’s constituency home may have been worth substantially less than the £650,000 valuation under which she sold a stake to her disabled son’s trust to buy a seaside flat, it emerged yesterday.

The former Deputy Prime Minister bought the detached house in Ashton-under-Lyne, Greater Manchester, for £375,000 in 2016 along with her then husband, Mark.

When they divorced two years ago, half of its value was transferred to a trust benefiting their teenage son, who was left with lifelong disabilities after being born prematurely.

In January this year Ms Rayner sold her 25 per cent stake to the trust for £162,500, using the money as a deposit towards an £800,000 flat in Hove, East Sussex.

But analysis of property sales data has put the house’s £650,000 valuation in 2023 into question.

Out of 44 homes sold in the street in the last five years, the most expensive was a semi-detached property which fetched £265,000 – almost £400,000 less.

The most recent sale of a four-bed detached house within a mile of her property was in May this year, when it fetched £425,000.

No property at all outside of Rayner’s street within a one-mile radius has sold for more than £561,000, according to analysis of Rightmove data. Estimates of the four-bed detached house’s current value on property websites range from £565,000 to £637,000.

And a local estate agent told the Daily Mail it could now be worth between £527,000 and £620,000. 

If the property is worth less than the valuation used by Ms Rayner, it means that were it to be sold, her son risks getting less back than the trust in his name paid his mother.

The trust was set up after a compensation payout from the NHS following difficulties during his birth and subsequent care in 2008.

The red-brick house – described as ‘imposing’ in an estate agent’s brochure when it was marketed for £400,000 in 2016 – is larger than the mainly semi-detached and terraced homes in her street.

It is set in what are described as ‘substantial’ grounds – the garden is so large that it adjoins houses several doors away, leading to one neighbour claiming Ms Rayner’s trees are blocking his light.

The Rayners have built a 6 metre (19ft 6in) extension – an extension typically adds 10-15 per cent to a house’s value. Ms Rayner’s allies have insisted the house was valued by a third party, likely a professional valuer, who would have considered improvements to the property.

Earlier this week Ms Rayner said she transferred her share of the house to her now 17-year-old son’s trust in order to ensure he had ‘stability in the family home’.

She and her ex-husband alternate living at the property and look after their two teenage sons under a ‘nesting arrangement’, she said.

Stephanie Churchill, founder of Churchill Taxation, said when a property is put partially or wholly into a trust, there is often no need for a formal surveyor’s valuation.

But if the share is sold, Ms Churchill said she would advise on a ‘robust’ surveyor valuation.

‘If she has taken more money out of the house than she should have done, that could have tax implications,’ Ms Churchill added.