Kevin White, 51, and his wife Allison had packed up their house and had been quoted £660 from Bristol 1st Removals to help transport their things.
But on the day of the move, there was a delay in the couple getting the keys to their new house.
And when they phoned the removals firm to let them know, the company said they would have to store the couple's items overnight - at an extra cost of £1,920.
The furious couple ended up forking out a whopping £2,500 to Bristol 1st Removals - but not without threatening to call the police during a heated discussion.
However, Richard Morgan of Bristol 1st Removals said that, under the company's terms and conditions, they acted within their rights and legitimately charged the extra money.
Mr White, a driver, told how he and his wife had planned to move on October 18 from Ilchester Crescent in Bedminster Down, Bristol, to Chessington Avenue in Whitchurch - a 15-minute drive away.
He said: "At 11 o'clock our solicitor phoned and said the guy buying our house had a delay with the money. We phoned the removal men and they phoned up their boss."
Mr White said Mr Morgan then rang from the company and told him that, under the terms and conditions, there was a cut-off time of 3pm for moving.
The company said that if the keys weren't available possessions would have to be stored overnight.
Mr White said: "I was told to pay £1,920 on top of the £660 and if I didn't pay it I wouldn't get my stuff back.
"I paid the £1,920, which came to a total of £2,500 to move four miles."
Mr White said he had the keys to his new home by 4pm, but by then it was too late.
He and his wife stayed the night at their son's home in Bedminster Down before the move was completed the next day.
He said: "Obviously we were angry. We chatted to them a week after and there was a heated discussion and I threatened to call police."
But Mr Morgan said that Mr White was "bang out of order" in threatening company staff, which contributed to him not meeting with the dissatisfied customer.
Mr Morgan said:"He got his keys late, we have terms and conditions and we reserved the right to charge more money."
He said he had not met with the customer since as he (Mr Morgan) had been ill, and had not appreciated him threatening his staff.
But he said he would speak to Mr White if he wanted to see him.
He added the company is a member of The National Guild of Removers and Storers Ltd and Mr White would be able to take any complaint to the Removals Ombudsman.