Emergency pods could be a useful tool to help people sleeping rough, a homeless charity has said.
The pods in Newport provide individual, portable, insulated shelter with a key coded door.
Charity The Wallich said it would welcome more like them, but the project has been turned down for a Welsh Government grant.
The government said it was investing more than £30m in tackling homelessness over two years.
Wayne Evelyn, 39, became homeless 10 years ago when his relationship broke down.
"There's no end to the places I've slept," he said.
"I was staying awake walking the streets, I was scared to go into hostels sometimes because things get stolen, and what little you have got you don't want to lose - when you're homeless what little you have got, means double to you."
Mr Evelyn said he still managed to make it to his shifts at a bakery, but the stress of not having a home led to a confrontation with someone he was staying with and he was jailed after admitting grievous bodily harm.
"I'm very sorry for what happened," he said.
"I wish I could apologise for what I've done every day. I'm glad that I've done all these [anger management] courses and I've learned how to be a part of society now.
"The only reason it happened is because I was homeless - if I wasn't homeless I'd never have ended up in jail."
Mr Evelyn also found it difficult to manage some living situations due to anxiety, which he now has medication for.
"The majority of the time if they offer you a place, you must accept it," he said.
"But sometimes you see things that happen, you get scared and you don't trust anyone. When you suffer with anxiety it's difficult to be around people you don't know."
But Mr Evelyn added if the pods had existed, he would have used them.
"If you're in a place where you can open the door and you can shut the door, you feel safe," he said.
The Amazing Grace Spaces project is seeking alternative funding, and Stuart Johnson said the idea came after years of working in night shelters and asking those sleeping rough what they wanted.
"Our vision is for people to stay overnight - to reach people who find it hard to engage because they've been on the streets so long," he said.
"With this, because they need a code to access it, they come back to you - you build up a trust, they can trust you, you can trust them and then help them and see how they want to move forward."
Lindsay Cordery-Bruce, chief executive of The Wallich, said: "They're definitely a useful tool, we'd welcome more of them - but the support has to be in place so that it doesn't just become somewhere else where somebody feels excluded.
"I think there's a misconception about homelessness out there we're talking about buildings, when we're actually talking about exclusion.
"The evidence and the science on this is really clear, it's about how we engage the person, rather than what sort of pod space or bed space we offer them.
"How we meet people in their own environment where they're comfortable, how we take services to them is the key to solving homelessness, rather than expecting people to navigate complex systems."
The Welsh Government said: "We will continue to work with Newport City Council and other partners to prioritise the most effective appropriate projects to support people to move off the street and into longer term housing solutions."
It was announced on Wednesday that an extra £1.34m over winter - including £25,000 for every local authority and specific funding for Cardiff, Swansea, Newport and Wrexham as they are the four areas with the most complex rough sleeping issues.