Maureen Dangarembizi, a 23-year-old Zimbabwean university graduate, stopped dreaming years ago.

“When you are young, you have dreams of how it is going to be if you study hard and get a good job - and then you end up like this, at the bottom,” she said as she trudged up the steps of a dingy building in the crime-ridden heart of central Johannesburg. “Now I just focus on each day. To remember how I dreamt of where we would be at this age and then see where we are is just too painful.”

Mrs Dangarembizi fled to neighbouring South Africa with her new husband, David Jakana, 30, about 18 months ago. They hoped to find a better life. Instead they found themselves at the bottom of the pile in a country where they are not welcome.

Zimbabwean refugees in South Africa, often unable to obtain official asylum status, struggle to find work and face brutal police harassment and resentment from local people fearful that they will take their jobs. On Tuesday, in the latest outbreak of xenophobia, a Zimbabwean man living in a slum outside Pretoria was burnt to death by an angry mob.

A brave handful have decided to return home to vote in Saturday's elections. Many more, despite wanting to see the end of Mr Mugabe, cannot afford the trip and are fearful that the South African authorities will close off the border once they go back.

Officially there are one million Zimbabwean refugees in South Africa but the real figure is believed to be double, even triple, that. Many are well-qualified professionals who end up doing the most menial of jobs and living in poverty in overflowing hostels and church halls. They send what little money they earn home for relatives.

“I was a primary school teacher, but my salary did not even cover my transport to work. David is a qualified engineer but he had not had a job for years,” Mrs Dangarembizi said.

After leaving Grace, their one-month-old daughter, at a crèche run by a church group, the Dangarembizis work 12-hour days as hawkers. They sell everything from sachets of soap and juice to cheap keyrings and name tags. “It is not a nice life, especially when you know that at home you could be, and should be, having a good job,” she said. “But we have no choice.”

Like other refugees they blame President Mugabe for destroying their dreams and robbing them of hope.

Susan Ngwariu, who came to South Africa three years ago, said: “We used to have dignity but he has even robbed us of that. We have nothing here but it is still better than there. That is how bad it is. We all want to go home and pray to God he loses. Only God can beat that man.”

Sitting in the half-light in the back room of the Central Methodist Mission, one of the main unofficial homes for Zimbabwean refugees in Johannesburg, Ms Ngwariu strained her eyes to make beaded keyrings that she sells for about 35p. “If I am lucky I sell five a day, and may be earn 25 rand (£1.60) ... I send it all back home for my children. I have six, they are living with different relatives ... We are all scattered now because of that man [Mugabe].”

Everyone is agreed that the moment Mr Mugabe leaves office they will return home. “If Mugabe goes, I will go home immediately. Even though the economy will not recover immediately, I will still go home because it will be better there than here,” said Max Muriuti, 25, a mechanic.

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