"I have seen people come in and start grabbing armfuls of stuff so no one else can get it," says Sherron.
"After a few visits they realise they don't need to be like that and later they will start to bring things in to donate themselves," she says.
The Koha Shed started as a small operation in Sherron's garage five years ago.
People donated goods so others who needed them could collect them for free.
Sherron's daughter-in-law Meegan Manuka and volunteer Tiraha Tui spread the word via Facebook and the concept was quickly adopted in other cities and towns around New Zealand and overseas.
Most people would find the idea of strangers rummaging about in their garage while receiving no personal gain an outrageous idea but Sherron Sunnex is not most people.
"If you are hungry she will scrummage through her own cupboards to make you up a little food parcel, if you have nothing she will make sure you leave with everything you need."
That is how Sherron's granddaughter described her when nominating her for a Pride of New Zealand award in May 2015.
The following month, the Whanganui River burst its banks and the Koha Shed would be at the forefront of assisting flood affected residents from their temporary base in Hakeke St.
Food, clothing, furniture and teams of volunteers armed with shovels and wheelbarrows were dispatched every day in the months following the floods.
In the midst of flood relief operations, while Sherron's son Kingi Manuka and volunteer Anton Houlahan were delivering furniture, they helped out a Gonville family who were unaware that their shed was on fire.
They rescued the family dog from the backyard and comforted the family until emergency services arrived.
The Koha Shed moved to its current location in the old Scout hall in Duncan St in December 2015 and the once bare backyard is now a thriving garden with raised beds producing healthy vegetable crops.
There is a pool of a dozen trusty volunteers who regularly sort and display the steady influx of donations, tend the garden, repair and maintain the building, make deliveries and more.
On a Friday, when the Koha Shed was closed for sorting and restocking, the place was abuzz with friendly chatter and activity.
Volunteers Lesley Thompson, Dale Henare, Jackie Green and new recruit Kath Barrett were busy sorting, folding and hanging clothing on the racks.
"I saw on Facebook that they were looking for new volunteers and it seemed like a really good cause to donate my time to," said Kath.
"I come here after I take my son to Kindergarten."
Lesley said she likes to sort and display the clothing well and discard garments that are not repairable.
"Sometimes we get things that are just no good to anyone.
"We may not be selling the clothes but people still want to wear things that don't have stains or holes.
"When people are struggling, they want to feel good and wear something nice."
Dale says her young son Kaylib likes to come to work at the shed with her during school holidays.
"He has autism and he loves to organise the displays.
"He's got a real a real talent for it too."
Jackie's little terrier Molly is trotting around supervising operations and out the back are two happy hens laying an average of three eggs a day.
The eggs are added to the supplies on the food table where there is produce from the garden and donations of tinned and packaged food collected from the City Mission for emergency food parcels.
"Sometimes it is hard for people to organise themselves to get to the food bank and children need to be fed," says Sherron.
"We get people in emergency situations at the weekend and it is important to make sure that they have some good nutrition to tide them over."
It is the kind of pragmatic approach that makes Sherron such a strong advocate and support for people whose lives are in disarray.
She knows what it feels like to be in a desperate place and openly shares her history of gang involvement, depression, addiction and time in prison.
Thirty years ago, she had a spiritual experience that led to a whole new way of being and an attitude that allows her to support others without judgment or expectation.
It has helped her to stay the course when people let her down by exploiting the charity they are offered or using the Koha Shed for personal gain.
"Some people have taken things from the Koha Shed for free and then sold them online for personal profit and we have had to ban people which can be disheartening."
Most people embrace the koha concept, and Sherron says the Whanganui community is exceptionally generous in their support.
Sandi Roach, maker of reusable fabric bags, dropped by to collect a big bundle of pillowcases that she will make in to bags for the Koha Shed.
Karen Calcott and Paul Gibbs of ExplorArtz also called in to discuss painting a mural on the Koha Shed fence and Sherron is keen to have a newly donated large horse float decorated as well.
ExplorArtz were winners of the Arts and Culture Award at the recent Trustpower Community Awards while the Koha Shed was presented with the runner-up award in the Health and Wellbeing category which Sherron said came as a complete surprise.
There was a catch in her throat when she described the Koha Shed as a place that "puts the 'unity' in community" during her acceptance speech.
"Knowing that we were nominated by a few people made me feel quite emotional," she said.
On the following Tuesday, the Koha Shed was open for business and children's clothes, bedding and toys were in demand.
One "customer" was looking for clothing suitable for an 18-month-old child.
"They are for someone who is new in town and she said her child is growing out of things.
"I just met her at a sports match and I thought I could help out by finding things for her because she is busy getting settled."
Sharon was looking for things for her grandsons who have just moved to town to live with their father.
"It's quite urgent because Oranga Tamariki [formerly CYF] removed them from their mother's care and they don't have much with them."
Sherron says it is great that people can come to the Koha Shed and find what they need without spending money they need for food and bills.
"It was our original reason for being here," she said.
Her daughter-in-law and co-founder Meegan is now a diving instructor working at different locations in the Pacific.
"She is based in Sydney but she goes off to different locations and she has recently been working in Fiji."
Fiji established a Koha Shed with support from Whanganui after Cyclone Winston left people devastated in February last year and there are now over 30 sheds operating around New Zealand, including the "sister shed" run by Belinda Harvey-Larsen in Marton.
She may be recovering from hip replacement surgery and dealing with the daily demands of running the Koha Shed as well as being a mother, grandmother and foster mum but Sherron says her mind is buzzing with new ideas to benefit the community.
"I think the surgery has given me a new lease of life," she says.
She wants to turn the horse float into a shop at the front of the Koha Shed where young people will gain retail experience to improve their work prospects.
"I want young people in Whanganui to have more options and I've got lots of ideas.
"I'd like to see a hunting and possum trapping venture as a way for young people to earn a living and help the environment.
"I'm also thinking about a rag trade project where youth could be trained and employed to run it."
Then there is her "Soup Love" project which she has already set in motion.
"I have been talking with Countdown about becoming a partner in their Food Rescue programme," she says.
The supermarket chain has partnered with community organisations to donate food that would otherwise go to landfill.
Their policy is to donate safe, high-quality surplus food to food banks and food rescue organisations.
"I have three people with food handling certification ready to work on turning food into soup for distribution in the community.
"I don't see myself doing it - I want to help get it started and then I'll retire and feel happy that it's underway," she says.
The Koha Shed at 88 Duncan St, Wanganui East, is open from 10am to 3.15pm on Tuesdays, Wednesdays and Thursdays. Find out more on the Facebook page.