Trish Mohrholz's day began like any other — the 71-year-old Port Pirie pensioner hopped out of bed, made a cup of coffee and switched on ABC Radio Adelaide.

But today she heard an interview with SA Treasurer Rob Lucas about a rental price hike for some SA Housing Trust tenants that would be in the state budget.

She said the hike would mean she has to pay an extra $10 per week for rent.

"This morning [I was] listening to David Bevan and Ali [Clarke] interview the Treasurer, Mr Lucas," Ms Mohrholz said.

"And I thought $20 a fortnight, that's a lot … that's a third of what I usually spend on my groceries.

"I thought, damn, I'm going to ring up, so I did."

Ms Mohrholz told the Treasurer about the struggle she would face following the rent price hike.

Mr Lucas replied: "We hear what she says, we see that there are problems there … I understand, I sympathise with the problem Trish has got."

The Treasurer conceded that his sympathies would not pay anyone's bills, and was asked by Bevan, "Do you have to have ice in your veins to be a treasurer?"

Mr Lucas replied: "Well look, it helps."

Ms Mohrholz said after hearing the Treasurer's remark, she had to hold back tears.

"If they didn't have icy veins they would understand and be more passionate about low-income earners," Ms Mohrholz said.

"Honestly, when he said that it was frustrating … I'm trying not to cry now because I get so angry and frustrated."

Pensioner can't afford 'a cup of coffee'

Port Pirie pensioner Trish Mohrholz was so outraged with the price hike on rent that she called into ABC Radio Adelaide. ( ABC News: Simon Royal )

Ms Mohrholz said she was thankful to get a Housing Trust home.

She had spent 13 years on the waiting list, and moved from Mount Barker, in the Adelaide Hills, to Port Pirie when she was offered a home.

But while the Government has argued it is fair, Ms Mohrholz does not quite see it that way.

After her rent of $88 per week, she is left with $628 in her pension per fortnight to live on.

She runs a car — a necessity, she says, in Port Pirie — and also helps support her two sons.

Ms Mohrholz tries to spend only $60 per fortnight on groceries, though that is not always possible. She rarely buys meat, only occasionally buying chicken.

SA Treasurer Rob Lucas handed down his first budget in 17 years in Adelaide on Tuesday. ( ABC Radio Adelaide: Malcolm Sutton )

The rent rise will come out of her grocery bill.

"I do know where the money is going to come from. I'm going to have to stop getting luxury stuff," Ms Mohrholz said.

"Once a fortnight I treat myself to something yummy to eat, I cannot do that normally, I can't even go and get a cup of coffee."

In the past fortnight the treat was an apricot delight, but Ms Mohrholz's favourite is a cream bun.

Ms Mohrholz said it was the thought of having to forgo those simple things that triggered her anger and made her call the radio station.

Rent increases to net government $2.6 million

The SA budget measure will increase rents for tenants of bedsit properties and one-bedroom cottage flats from their current rates of 19 and 21 per cent of household income, respectively, to a standard rate of 25 per cent.

The measure is predicted to affect 2,970 cottages, like Ms Mohrholz's, plus another 90 bedsit properties.

Currently, Ms Mohrholz pays 21 per cent of her income on rent. Starting from this November, that will rise incrementally until 2021, when tenants will be paying 25 per cent of their pension or benefit in rent.

The Government said each move would be limited to $10 per week. People on moderate employment incomes would be paying up to 30 per cent.

Forced to defend the move as being in line with interstate charges for public housing, the Government expects to raise $2.6 million.

"The former government and this Government sees 25 per cent as a not unreasonable contribution to a subsidised Housing Trust home," Mr Lucas said.

"The Government has made a decision in relation to what's a fair payment for subsidised housing rents."