Deadly flooding has left a mammoth clean-up task after lashing parts of NSW, resulting in five deaths, damaging up to 10,000 properties and cutting off tens of thousands of people in regional towns.

Locals and emergency services are assessing more of the damage on Sunday.

WATCH THE VIDEO ABOVE: Flood clean-up begins in NSW.

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Daniel Fitzgerald slept in his car for five days, watching helplessly as floodwaters slowly destroyed everything inside his home for the second time.

The deluge did not spare Fitzgerald’s home at Taree, on the state’s Mid-North Coast, which he shares with his four children and brother Michael Forbes, who has a disability.

“I was devastated - there’s nothing you can do. You can’t stop water,” he told AAP on Saturday.

Water lapped the front of the old weatherboard house before inundating the property, forcing Fitzgerald to wade through waist-deep waters to survey the devastation.

The brothers were already mourning their mother, who died in April.

“It’s just like losing my mother all over again. It’s heartbreaking,” Fitzgerald said.

Furniture, clothes and kids’ toys were destroyed but losing precious mementos to the floods - including USB sticks containing family photos and videos - was devastating.

“We didn’t have time (to prepare). I got some clothes out but that’s it,” Fitzgerald said.

The family expects it will cost more than $150,000 to replace the damaged goods, while Forbes, a keen vinyl, comic book and DVD collector, lost up to $100,000 in items.

The destruction brought back unwanted memories from four years earlier, when their home last flooded.

“The first time we had insurance and it took them over two years to repair the place,” Fitzgerald said.

“It was stressful the whole way through just trying to get them to do anything, even though we paid insurance for years.”

This time, there’s no insurance policy to fall back on.

The family’s previous insurer refused to cover them again, while others had unaffordable prices of up to $15,000 that did not cover flood damage, Fitzgerald said.

Family friend Sharon Revell organised a GoFundMe to help the family get back on its feet.

“Seeing them go through the loss of (their mother) and then this so soon after, they haven’t had time to grieve,” she said.

“The last flood was a one-in-100-year flood and this flood is a one-in-500-year flood four years later.”

Kempsey Shire mayor Kinne Ring, whose council covers parts of the Mid-North Coast, said insurance premiums had skyrocketed with recent floods and bushfires.

“For many, it’s unaffordable or they live in locations where you actually can’t get insurance,” she said.

“All of these things create enormous financial and emotional stress that makes this flood even more difficult to come back from.”

Port Macquarie resident Margret Meagher still doesn’t know the fate of her home after evacuating to her partner’s house six days ago.

While waiting for a ferry to be restored to take her home, Ms Meagher recounted the “eerie” days she spent in her house during the previous floods.

“It’s a bit like when your house gets burgled - the safe place you align with as a home and a place of rest becomes a bit of a battleground,” she said.

Yards resemble rubbish dumps

The front yard of the home Damian Newell and his family were forced to leave amid rising floodwaters has turned into a rubbish dump as their town continues to clean up.

Newell and his family evacuated their Taree home on Tuesday afternoon before the Manning River reached its highest level on record.

“Our front yard at the moment looks like a rubbish dump,” he told AAP.

Some sentimental items placed up high survived.

“All the mattresses and everything, that’s all gone.”

“Ridiculous” quotes for contents insurance at the rented home were too much.

“We ran the risk, it is what it is,” Newell said.

But support from the community has been almost overwhelming.

“I know there’s others out there that are worse off than us by miles.

“It’s a pretty big, costly clean-up for us all.

“We’ve just been cleaning up as best we can and trying to see what we can salvage.”

His immediate focus was on trying to restore some normality for his three children.

“They’re a bit devo that they’ve lost most of their toys and stuff like that.”

Up to 50,000 people still isolated

The SES has conducted 200 resupply operations in recent days to cut-off communities, including parts of Kempsey, Port Macquarie, Dungog, Port Stephens, Maitland, Central Coast and Nambucca Valley.

Up to 50,000 people are estimated to be isolated.

The agency responded to more than 7200 incidents and conducted 774 flood rescues.

Assistant Commissioner Allison Flaxman said almost 10,000 properties had been flooded, with damage assessments beginning on Saturday.

“Please allow damage assessment to take place before you begin to washout your property.

“We need to evaluate the extent of property and infrastructure damage to ensure your property is safe to return to,” Ms Flaxman said.

Premier Chris Minns visited Taree and said the state government wants to help the community get back on its feet as soon as possible.

Hardship and disaster grants are planned to become available in the coming days and efforts to improve flood resilience in Taree and other communities will follow.

But previous attempts, while well intentioned, had not always delivered in areas hit by flooding.

“We’re determined not to repeat the mistakes of the past, given we’re having more and more of these natural disasters,” Minns said.