Three robbers who tied up and killed a wealthy property owner at his own home for his £25,000 Rolex are facing years behind bars.

The gang targeted reclusive businessman Milton Papadopoulos in his home in Parkfield View, Potters Bar, after hearing how he spent large sums of cash on high-class escort girls.

Posing as builders driving a white van, they knocked on his door before bursting in and restraining him with handcuffs around his wrists and ankles.

The 41-year-old victim’s next-door neighbour heard him screaming “like something out of a horror movie” but decided not to call police.

Mr Papadopoulos was found smothered to death two days later when his sister went round to the ransacked house in October 22, last year.

Sebastian Oskar Kimel, 40, was convicted of murder while both Krzysztof Kasza, 42, and Arkadiusz Szarkowski, 42, were both found guilty of the lesser alternative of manslaughter.

The family of Mr Papadopoulos were not at the Old Bailey for the verdict because it was the anniversary of his death.

A fourth suspect, Wojciech Ryniak, was himself murdered in Barton, Oxford, in April.

Kimel, Kasza and Szarkowski will all be sentenced on Friday.

Mr Papadopoulos earned around £8,000 a month from his rental properties and was also involved in a property management company, a double glazing business and selling security cameras on eBay.

He became reclusive after his relationship ended in January 2012 and began taking a lot of cocaine, gambling away thousands of pounds online and paying for escort services.

During the trial it emerged the owner of an escort business told Szarkowski that Mr Papadopoulos paid for the girls using cash stashed under a sofa and in a wardrobe at his home.

Four weeks before the murder, on September 26 last year, the mobile phones of all three men visited the area of Mr Papadopoulos' home between 1pm and 6pm.

Then at around 10.25am on October 20, a 17 year-old neighbour heard loud knocking followed by Mr Papadopoulos saying: 'You're not allowed in, don't come in'.

Moments later she heard the victim 'scream a scream I had never heard before, like something in a horror movie'.

She took a picture of a white van parked at the end of the drive and texted a friend: 'my neighbour has a white van outside his house and I keep hearing him screaming… so much shit happens at his house he’s so fucked up x'.

After receiving the reply 'Might begettingrobbed xx', she texted: 'Nah they been there for a while now… He’s a druggy and all depressed… he might owe money or something I dunno xx'.

Mr Papadopoulos was found dead by his sister Jenny Michaelides on the evening of October 22 after failing to answer calls and messages.

The house smelt of disinfectant and showed signs of being searched and cleaned up.

Mr Papadopoulos was lying naked on his back in the lounge with 'dark stains' on his wrist suggesting the use of handcuffs or other restraints.

The postmortem revealed evidence 'consistent with something being held over his face' until he was smothered to death.

Mr Papadopoulos' white gold Rolex Submariner watch valued at £24,700 was missing.

Kimel, who was linked by DNA to the scene, claimed he visited the victim's home to collect a debt of 2kg of cocaine and £100,000.

He refused to name his boss out of fear of reprisals on his family but blamed the killing on Ryniak.

Kimel told jurors that Ryniak “lost control” and began hitting both him and the victim, breaking Kimel's nose and briefly knocking him unconscious.

He added: “I saw Milton lying down there and something strange was happening to him, he was fading away.

“His eyes were rolling back into his head. I knew that there was something wrong. I panicked, I knew that something wrong was happening.”

Kimel claimed he tried to save Milton's life before going outside to the van.

Both Kimel and Szarkowski denied any knowledge of a plan to rob the victim or cause him any harm.

Kasza claimed there was a plan to steal Mr Papadopoulos' money while he was out of the house.

Kimel, of Beechcroft, Streatham, south London, denied and was convicted of murder and conspiracy to rob. He had already admitted conspiracy to falsely imprison.

Kasza, of Imperial Road, Wood Green, north London, and Szarkowski, of Abbs Cross Gardens, Hornchurch, Essex, were both acquitted of murder but convicted of manslaughter, conspiracy to rob and conspiracy to falsely imprison.