Watch: Antiques Roadshow expert is left speechless over 'incredible' 300-year-old dolls' house worth six-figures

It's very rare an antiques expert is completely lost for words when faced with someone's extraordinary find.

But Fergus Gambon was utterly stunned when a man presented him with a 311-year-old Westbrook dolls' house during an episode of Antiques Roadshow, saying it felt almost "impossible" to value the rare heirloom.

Stream episodes of Antiques Roadshow for free on 9Now.

During the episode – which you can stream for free on 9Now - we watched on as Fergus explained that the man in question hadn't even brought in the house for inspection.

"You arrived here this morning and you were clutching a little cardboard box with three dolls in it," Fergus said.

"Then you mentioned those dolls lived in a house. I thought to myself... if those dolls live in a house as old as the dolls, we're talking something quite incredible."

Watch the incredible story in the video above.

The man went on to explain that the dolls' house was built in 1705 by tradesmen on the Isle of Dogs for a lady called Miss Westbrook, and it's been in his family since that time.

Truly astonished, Fergus revealed the team made the unusual decision to jump in their cars and visit the man's home so Fergus could see the dolls' house for himself.

Watch the moment he saw the doll house for the first time in the video above.

"There is no other like it, it's totally unique," Fergus explained.

"It's quite unorthodox for the Roadshow, because the dolls' house was in your house. Like never before, we trailed over and I looked at it.

"When I opened it... those panelled rooms and that wonderful furniture. I was looking at something that was essentially unchanged for 311 years.

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"Something that was made as a toy, that could so easily have been spoiled... that's why it's so moving."

Fergus said that when he saw the house for the first time, he recognised it. "It was something I laid in bed dreaming I might see," he said.

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The expert then picked up a little furniture chest in the house, explaining that while the outside was faded from natural sun exposure the inside was more bright and colourful than ever.

"I've found the whole day today completely staggering and amazing. I never, ever felt I would see such a wonderful..." Fergus said, lost for words.

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When it came down to valuing the home, he hesitated: "It's an impossible task..."

See the valuation in the video below.

But after deliberating for a moment, he announced: "For the house with its contents, we're looking at a conservative estimate of £150,000, maybe £200,000 (approx AU$191,000 to $382,000)."

"That's... pretty astonishing," the man replied.

Stream episodes of Antiques Roadshow for free on 9Now.

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