Three men approached the 82-year-old victim while he was in his garden on Woodfield Road, Harrogate, around three weeks ago and offered to fix his dormer bedroom window as it appeared to be leaking.
The men, who said they were from Pateley Bridge, gave him a price of £86 for the work and spent four days doling the job. When they had finished they said the cost of the work had gone up to £1,200.
One of the men took the victim to the bank, where he withdrew the money, while the two other men waited at his house.
When the men had left, the victim noticed that £500 which he was saving for a holiday had been taken from a vase in his kitchen.
The men are all described as white. One was over 6ft and another of the men was around 5ft 5in tall. The third man stayed in their unmarked van for the duration of the work. All their equipment appeared to be new.
Officers are appealing to anyone who has any information that can help to identify the men, to contact them as soon as possible. They would also like to hear from anyone who has been approached in similar circumstances.
For more information about protecting you and elderly neighbours against doorstep crime, visit www.northyorkshire.police.uk/boguscallers
Alternatively, information can be emailed to Amanda.Hanusch-Moore@northyorkshire.pnn.police.uk
If you prefer not to give your name, Crimestoppers can be contacted anonymously on 0800 555 111.
Please quote reference number 12150107993 when passing information about this incident.