Distressed unit owners in a cracked Sydney building are coming to terms with a bill of more than $1m for emergency repairs and other costs, as the New South Wales premier called on strata and building managers to “step up”.

Mascot Towers, in the city’s south, was evacuated on Friday night after engineers became concerned about cracks in the primary support structure and facade masonry of the 10-year-old building on Bourke Street.

Residents in about half the 122 units considered partly accessible have since been told they can briefly return to collect personal items under escort.

All of the other units fall in the non-accessible zone and cannot be entered, along with car parks, recreational areas and some businesses.

A document from strata management company Strata Choice, advising owners of a meeting on Thursday, reveals they will need to pay a special levy of $1.1m, or thousands of dollars per unit, by 1 August.

The document breaks down costs, without GST, into $254,000 for propping, $250,000 for engineering, $176,000 for legal fees, $100,000 for the estimated cost of the evacuation, $70,000 for new carpets, $5,000 for a media consultant and others.

The premier, Gladys Berejiklian, said the government was looking at whether there were any flaws in the system that have led to the situation.

While the root cause was to be determined, she reiterated the entire industry - including the way buildings were certified and compliance measures – will be overhauled, with legislation to be passed by the end of the year.

The government was also working “overtime” to install a building commissioner, Berejiklian said on Wednesday.

“I appreciate the frustration those residents are feeling but I also ask all owners, corporations and building managers to step up and make sure they’re doing everything they have to according to the law.”

Her comments came after the owners of 24 units within Mascot Towers on Tuesday wrote to the management of their building to demand further access to the building and information from engineers.

They said the “chaos” following the evacuation has put residents in “varying states of distress, not to mention extreme mental and financial duress”.

“We have to express our disappointment and dismay over which the evacuation was handled; there has been a shocking lack of leadership and emergency planning when this crisis happened,” they said in an email.

An update from building management on Monday night reiterated that a claim on the building’s insurance policy to fund temporary accommodation had been knocked back.

It’s been reported the building is too old for warranty cover.

Residents and owners are scheduled to meet with experts and government officials on Thursday night.