I'm trapped in a retirement flat with a £20k service charge. I fear I'll never sell

"It's very humbling, it's very scary… you know I'm nearly 58 and never thought I would be in this situation," she says.

After taking legal advice, Woods made plans to move in, but was then told by the management company she was too young to live in the property.

The flat in Tewkesbury, Gloucestershire, has been on the market ever since but there have been no serious offers.

Woods is being asked to pay service charges and ground rent, with the possibility of a debt recovery agency being brought in to collect the money.

"I was shocked. It didn't make sense; I'd inherited it, the title was legally mine, I was willing to pay the fees and I was over 55."

Woods now lives two and a half hours away and can only afford to rent a bedsit.

In a statement, Firstport Property Management said it is working with Woods "to support her at this time".

But insisted that despite the death of her mother and the flat remaining empty, service charges still apply.

"We are required to pursue recovery to ensure these funds remain available."

Elsewhere, we also found more evidence of flats in desirable locations which have lost tens of thousands of pounds in value.

One development, Goodes Court in Royston, Hertfordshire, stood out.

It's a block of 52 flats for the over-70s run by McCarthy Stone, the biggest supplier of private retirement developments in the country.

It has extra facilities such as a dining room, on-site manager and cleaners.

The service charge is typically £10,000 per year for a one-bed flat.

By analysing Land Registry records we found that of 27 flats sold since 2014, 24 fell in value, losing a total of more than a million pounds.

For example, Flat 33, which first sold for £208,000, was bought two years ago for just £70,000.

Another, Flat 25, had an original asking price of £192,950 and resold last year again for £70,000.

And Flat 36, which first sold for £189,950, is now at auction with a sale price of just £9,000.

McCarthy Stone is building another development of flats for the over-60s, 400 metres away in the centre of Royston.

The company told us many of its properties retain or go up in value but recognise that that hasn't happened at Goodes Court.

It said it had invested in "significant refurbishments" to support owners who were free to rent out flats while trying to sell them.

However, it insisted across its other developments "the overwhelming majority of residents and their families are delighted with their experience".

Woods says it all "feels very inhuman… just about balance sheets and profit and loss".

And Fraser says he'd like to warn anyone looking at buying a retirement flat in a development to think very carefully.

"Before, I would have said, yeah, go for it. Now I'm saying be very, very careful. It may not be as wonderful as you think it is."