"But there are days if I wonder whether I should continue because of the toll it takes on myself, my health, my family and my staff."
It's not just the imbalance of Manning and law students against NZ Defence Force's Special Inquiry Office with 11 staff.
There's a financial gulf. On one side is Manning and meagre legal payments through a process which appears to have been flawed. The inquiry started in May - there was a gap of seven months before being paid some money and nothing again since then.
On the other side is NZDF's $2 million to pay for its investigators, lawyers and researchers.
"It's got to the point where it's just not tenable," says Manning. "We're talking about funding to pay for the cost of running a practice - to put up shelving for files, to pay interpreters, to pay staff.
"I have a revolving mortgage so I lean on that. And I cross my fingers and hope we get something.
"It's not a reasonable approach - particularly not when your counterparts seem to have unlimited funding.
"It's a daily anxiety…"
Fight to free Zaoui
It's a grim place for a human rights lawyer recognisable for the high-profile fight against the internment and persecution of Algerian refugee Ahmed Zaoui over a decade ago.
It took years of bloody-minded stubbornness and faith in the law to cut through the obfuscation and stone-walling of the intelligence agencies who claimed her client was a terrorist.
For the duration, Zaoui's case was seen as an impossible fight. Across Western nations, the September 11 attacks cast a shadow over open justice, leading to closed court hearings amid concern over national security.
Manning swam against public opinion for years until, ultimately, vindication when Zaoui was freed to live a normal life.
And an admission from Sir Michael Cullen - Deputy Prime Minister during the saga - who, in previously unreported comments from 2016, said: "I think at the time we in government were too willing to accept what we were told instead of probing behind the true nature of the source of that information and therefore its inherent unreliability."
So here she is again, Manning and a handful of similarly inclined lawyers against the world, the establishment, the secretive world of spies and the long shadow cast by the War on Terror.
The journey to this point began with the book Hit & Run by Nicky Hager and Jon Stephenson.
It detailed what was called Operation Burnham - a 2010 NZSAS raid into Taliban territory to hunt down those who were launching attacks against NZDF personnel in neighbouring Bamiyan province.
The book detailed the planning and execution of the raid - NZDF says it contains 105 errors - and how US air support left villagers dead and wounded.
NZDF, in contrast, says nine insurgents were killed. It also concedes civilians may have been killed, after years of letting former Defence Minister Wayne Mapp's assertion to the contrary stand.
"They need a lawyer"
Manning was drawn into the case after an approach by the authors of Hit & Run. Knowing her track record in New Zealand and overseas in humanitarian cases, they told her the villagers - of whom some had been interviewed for the book - needed a lawyer. Would she take it on?
"One of the reasons I took this case on was my ethical belief we are all equal to each other," says Manning.
"Do I want to live in a country that could be responsible for the death of a little girl and not own up to it?"
Manning likens herself to a physicist with a fascination for the immutable Rule of Law. Legislation, once fixed, provides an intractable framework which governs the type of society we live in and the type of world we want.
"I realised I'm somewhat a legal physicist. I'm interested in the Rule of Law. What are the rules of law that can't bend and how do we learn to interact with them?"
Her area is law needed most by those in extreme situations - the most endangered, the most vulnerable.
Calls for an inquiry under the National Government went unheard so Manning lodged a case on behalf of the villagers with the High Court. When the incoming Labour-NZ First Government announced an inquiry, the High Court case was pulled as a show of "good faith" towards the Inquiry into Operation Burnham.
It is the first such inquiry in New Zealand to examine the operational activities of our armed forces.
Even though Afghanistan cost New Zealand 10 lives, 10 years and $360 million, there hasn't been a single published inquiry into our contribution and whether it was well-managed.
NZDF carried out one inquiry into the Bamiyan provincial reconstruction team through its "lessons learned" department. The report was critical of command decisions - it was shelved in draft form by commanders who judged it too inaccurate to be released.
Each of our Five Eyes partners - Australia, Canada, the United Kingdom and United States - have carried out a number of inquiries through which their citizens have learned what was done in their name.
New Zealand, alone, has yet to do so although a review is said to be under way by the Ministry of Foreign Affairs and Trade with the Ministry of Defence.
Until then, all we have is the Inquiry into Operation Burnham.
And all the villagers of Khak Khuday Dad and Naik have is the law. And Manning.
"Human rights matter"
"Fundamental human rights matter to a civilised society," says Manning. "It matters to my clients to have a proper investigation into what happened to them."
Through her legal work - humanitarian and immigration - Manning has friends in the Afghan community.
It makes the case real. She has thought on how devastating it would be were they to be killed.
For most in New Zealand, she wonders if this is not the case.
"I've been wondering how this compares to the Zaoui case. There's something harder about this one.
"In the Zaoui case, he was in the country. You could see him. In this case, my clients are out of the country - out of sight, out of mind."
In her view, is has been a struggle to make those people real to the inquiry heads, former Prime Minister Sir Geoffrey Palmer and former Supreme Court judge Sir Terence Arnold.
When the first public hearing was held in November, she pushed for the inquiry to accept it would conduct a "right to life" examination, which would shift the focus to those affected by the NZSAS raid rather than an inquiry into the actions of NZDF.
Without it, her clients have been cut out of the evidence and information loop when, as Manning sees it, they should have box seat.
Information has been judged as too classified, despite being made available in comparable countries, and the NZSAS too vulnerable from a security perspective, to be cross-examined - even though exactly that has happened in New Zealand courtrooms.
Arnold and Palmer's decisions so far have leaned heavily on submissions from NZDF and government agencies which warned of the dire security consequences an open process posed.
In a minute issued today, Arnold and Palmer said there had been concerns the inquiry would be a "whitewash".
"This concern is misplaced. We are confident that, utilising its intended process, the inquiry has the capacity to, and will, get at the truth, whatever that may be."
To the High Court
Today, Manning effectively withdrew her clients from the inquiry and sought a High Court view on whether Arnold and Palmer were wrong.
Manning: "In my view, this should be a process centred on those affected by Operation Burnham, those who were injured or killed.
"The names of our clients are never talked about. The death of Fatima is not acknowledged. She is not even mentioned."
Those international laws look very distant in the legal papers filed today with the High Court, seeking a ruling that the inquiry's rejection of a "right to life" inquiry was unlawful.
There's the International Covenant on Civil and Political Rights. The Minnesota Protocol on the Investigation of Potentially Unlawful Death from the United Nations High Commissioner of Human Rights.
Distant, yet still agreements and international bodies to which New Zealand signed up and, in doing so, enjoyed better international standing as a country which took human rights and the rule of law seriously.
Manning's argument is that these agreements, and the Bill of Rights, compelled New Zealand to launch a full, independent inquiry into the NZSAS raid as soon as reports of civilian deaths emerged.
The inquiry, she says, provides that opportunity. And if it doesn't, then Attorney-General David Parker failed when he set the Terms of Reference. And if that is so, then there must be some other inquiry established which does so.
On funding, a spokeswoman for the Department of Internal Affairs appeared to concede it had got it wrong when it came to funding Manning, and the other non-Crown participants in the inquiry.
"There is very limited precedent under the Act for granting funds for legal assistance, and we are working on improving our processes."
In total, $156,730 has been granted for legal assistance in the year since the inquiry was launched.
Manning received $50,000 after seven months of no pay, shared between five lawyers. Hundreds of hours of work have gone unpaid for 21 named and signed up clients who, since the 2010 attack, have scattered, leaving ruined homes and a village which became a war zone.
There's no such thing as quick instruction from clients. Communication is difficult, it's a dangerous country and the environment is harsh. The lawyer's investigator is currently blocked by snow. Some clients have found work down coal mines - inhospitable workplaces in an inhospitable land.
"They have no funds. They are impoverished. Our clients are below the poverty level.
"It's a compelling case," she says. "These villagers are very clear about what happened to them on that night. This village had been there for hundreds of years. In a night, their lives were destroyed."
A spare room, door slightly ajar, reveals stacks of cardboard boxes threatening to spill files to the wooden floor. A knock at the door of the Westmere bungalow signals a law student turning up to work at the kitchen table alongside Manning.
In Wellington, NZDF has Paul Radich QC on $546 an hour.
"We have a crisis in New Zealand for access to justice. It is a known crisis," Manning says.
Similar sentiments have been increasingly voiced in speeches by superior court judges over the last decade, including the incoming Chief Justice Helen Winkelmann.