Image caption Carlos Blanco is now a volunteer at the centre where he was once a guest

As homeless charity Crisis opens its Christmas centres to those in need of shelter, former and current guests share their stories.

Carlos Blanco is 45 years old. This year he is at the centre in Chalk Farm, north London, as a volunteer. But two Christmases ago, he was a guest.

"I'd lost my job - I'd been struggling with agencies to get the shifts and then I was kicked out of my flat," he says.

After being a guest, he said he'd made a promise to himself to return to the centre - if not as a resident, then as a volunteer.

"I've got that understanding of how people feel. I can give them hope."

The Christmas centre is a volunteer-led operation offering guests a bed, bathroom facilities and three meals a day.

"You get a good night's sleep, you're warm and there's somewhere to shower every day. You just feel human again.

"There's a sense of unity here. But when you leave, you lose all of that all over again and it can be difficult."

'Never give up'

In summer 2015, after a stint staying with family, Carlos returned to London knowing he would be homeless.

He got work, but could not pay for somewhere to live: "I was paying myself to live on the streets. I was staying in a tent on Hampstead Heath.

"I would try and keep myself clean. But then you have people saying 'You don't look homeless'. What does a homeless person look like?

"You only think about the day you are on. Isolation is one of the biggest things to deal with. You have to be psychologically strong."

A report from Crisis has highlighted the number of street sleepers who have been victims of violent attacks and abuse.

"I'm angry," Carlos said, responding to the report. "People need to take a minute to understand, to wonder why this person might be in this situation.

"You never feel safe. You're open to everything. There's still, and always will be, that stigma."

Eventually, Carlos was picked up by the charity service Street Link who got him into private accommodation.

Things have got better - he says he's one of the "lucky" ones. A rekindled romance means he's now living with his childhood sweetheart. After 26 years of no contact she saw him on television on a Crisis campaign and tracked him down.

So what advice will he be giving the guests he meets this year? "Always keep pushing. Never give up."

Image caption Guests are offered a range of services at the Christmas Crisis centre

Ian is in his sixties. This will be his second Christmas at a Crisis centre and he has his "shopping list" ready.

Top of the list: A haircut. Then a massage and finally, podiatry. These are all services offered at the centre over the next week.

When he's not at the centre, he rotates around the city's churches, staying in a different one each night.

Getting out his phone, Ian scrolled down pages and pages of sent emails. They are all job applications. He said he applies for 10 a week.

But Ian is optimistic. He said: "One day someone will turn around and say 'Well, he's applied for this 20 times, let's give him the job'."

Image caption Corky said being homeless can be 'overwhelming'

Former psychotherapist Corky was homeless for five years. He was a guest at the centre last Christmas and said the facilities it offered, like a shower and a bed, were the "small steps" that can help break the "snowballing effect" of feelings of isolation and self esteem that can come from homelessness.

Corky would often base himself in Leicester Square, but sleep on trains to be safer.

"When you're on the street it's hard to value yourself. In our society, money is synonymous with value - human value. These are mindsets we have to move on from.

"If you sit now and think about what it is to be homeless, it's overwhelming."