Inside Natasha Malone's three-bedroom rental home are three beds in the front lounge room — for herself and two of her eight children.

The single mother has been told she will need to find a new rental by December because her current place will soon be up for sale.

In the meantime, her landlord has increased the weekly rent from $360 to $500.

To pay for the 38 per cent rent hike, Ms Malone has been forced to cut back on petrol and childcare expenses, get food from charities and stop medication for her recent cancer diagnosis.

"To be hit with a $140 increase in one go, it was really extreme," Ms Malone said.

"I now have to say what's more important, having a house or medication? And currently it's having a house."

Her rent alone takes up half of her fortnightly Centrelink payments of $2,000.

A chef by trade, Ms Malone stopped working after being diagnosed with cervical cancer.

She has applied for 46 new rentals in the past four months but has been rejected for every single one.

"What the real estate agents are saying is that everyone's offering more, like $100 more a week, and if you're not in a position to be able to do that, it makes it really defeating," she said.

"I'm worried that we're going to end up on the street and have nowhere to go."

Strong Adelaide rental market

Low supply in the Adelaide rental housing market, coupled with high demand, has driven rent prices through the roof.

The latest CoreLogic data shows Adelaide has the lowest vacancy rates in the country, while rents have grown by 4.3 per cent between April and June this year.

Real Estate Institute of South Australia director Adam Blight said the squeeze on the Adelaide rental market has been happening for the past 18 months as people chose to move to Adelaide during COVID.

"Everyone's losing out in this market at the moment. I think for every new tenant we're bringing on, we're potentially knocking back maybe 12 to 15 people that have also applied for the property," said Mr Blight, who is also Ouwens Casserly's property management director.

"We've seen our properties on market have actually halved in the last 12 months and at the same time we've seen applications on properties over doubled."

Yesterday, the SA Greens introduced legislation to parliament that seeks to cap rent rises in line with inflation.

But Mr Blight said limiting landlords from raising rent prices would not address the issue of low supply.

"It feels like the property market is not slowing down any time soon. Unless a whole bunch of properties come on the market all at once, then the supply issue is still going to be there and it doesn't seem like the demand issue is going anywhere," he said.

Renters living in cars

Renter advocacy group Better Renting wants the government to step in to control rent increases and to end no-cause eviction.

Campaigner Bernie Barrett said renters were reporting increases in weekly rent prices anywhere from $10 to more than $100.

"Renters are pushed out of their homes because their rent is increasing or the landlord wants to re-lease the place for higher rent. We are hearing people are moving back with family, living in their cars, living in caravan parks.

"We have a responsibility to make essential services accessible and equitable, and housing is an essential service."