Three Neighbours Split the Cost of Proving a Number Was Wrong

The situation

The plan had been simple enough three years earlier. Kasia, Agnieszka and Chamari, three retired business owners who had each spent decades running commercial rental properties around Uxbridge, jointly owned a parcel of land through a private arrangement, holding it as an investment they intended to eventually sell and split according to their original ownership shares. When a buyer finally came forward with an offer in the low seven figures, the three of them agreed the sensible path was to commission an independent valuation to confirm the split was fair before signing anything, rather than negotiating shares among themselves after the fact.

They retained a mid-sized accounting firm to produce that valuation. The firm was not a party to any agreement among the three neighbours; it was simply the outside professional they had jointly hired and jointly paid to produce a number everyone could rely on. The valuation came back, the sale closed, and the proceeds were divided according to the percentages the report set out.

Within weeks, Chamari raised a concern. She had commissioned a rough estimate of her own months earlier from a contact in commercial real estate, and it did not come close to matching the split the accounting firm's report implied. Kasia, who had put more capital into the property at the outset, was reluctant to revisit a number everyone had already agreed to work from, worried that reopening the valuation might shrink her own share if a recalculation favoured the sections she did not own. Agnieszka, caught between two people she had known for years, wanted the question answered but dreaded the prospect of the three of them ending up in a fight that could not be undone.

What none of them could get was an answer from the firm itself. The accounting firm, having been paid and having delivered its report, treated the engagement as closed and declined to walk through its methodology informally once a dispute among the three owners over the split had clearly emerged. Without the underlying working papers, nobody could tell whether the number was wrong, or simply lower than Chamari's informal estimate for reasons that had nothing to do with an error. All three of them wanted the same thing in principle, an accurate split, but three months into the disagreement they had stopped talking about the valuation at all and started talking about each other, which was the point at which Agnieszka finally suggested they bring in outside counsel before the friendship, and the property arrangement it sat inside, fell apart entirely.

The gap nobody had noticed

The three neighbours had a genuine dispute among themselves about how the sale proceeds should be split, but the evidence needed to resolve it sat entirely outside their own hands, in the files of a firm none of them had a lawsuit against and no contractual right to interrogate further. That is a common and often overlooked gap in disputes that turn on a professional's opinion: the people arguing about the number are rarely the people who can explain how it was calculated.

Ontario courts can order someone who is not the true target of a dispute to produce documents or sit for questioning, where those materials are relevant to an issue in dispute and cannot reasonably be obtained any other way. Because the three neighbours had no lawsuit against each other to attach that request to, the only way to reach the firm's files was to start a court application naming the firm itself as respondent, solely to seek the production order, without alleging that it had done anything wrong. This is sometimes called non-party discovery, and courts do not grant it lightly. A firm that has not chosen to be drawn into a dispute among its former clients is entitled to have that kind of intrusion justified, not simply requested.

Before any of that could be pursued, the three neighbours needed to actually agree on what they were asking for and why, which was its own problem. Kasia's instinct was to treat Chamari's concern as an accusation that she had somehow benefited from a rigged number, which was not what Chamari had said and was not something the facts supported at that stage. Agnieszka kept trying to broker a private conversation between the two of them that only made the disagreement more personal and less about the actual question, which was whether the report was accurate.

The legal fix, compelling the accounting firm's working papers, was straightforward to describe. Getting there required first turning three neighbours who had started talking past each other back into three co-owners with a shared interest in the same answer, because a motion brought by one of them against the others' objections was far weaker, and far more expensive, than one brought jointly. A court weighing whether to compel a non-party to produce its internal files is also, in practice, more receptive to a request framed as a genuine, shared need for information than to one that reads as a personal grievance dressed up in procedural language, which was one more reason the group's internal footing needed to be solid before anything was filed.

What we did

1. Met with all three neighbours together before drafting anything, to separate the factual question, whether the valuation was accurate, from the interpersonal one, whether anyone had acted in bad faith, because the second question was poisoning any chance of agreeing on how to answer the first, and needed to be defused before any legal step could work. That first meeting set the tone for everything that followed: nothing would be drafted or filed until the three of them could describe the problem the same way.
2. Reframed the dispute as a shared problem rather than a two-against-one accusation, pointing out that all three of them, including Kasia, had an interest in knowing whether the number they had all relied on was right, since an error could just as easily have cut against her as in her favour, which took the defensiveness out of the room.
3. Reviewed the original engagement letter with the accounting firm to confirm the terms under which the valuation had been commissioned, establishing that the firm owed all three neighbours a duty of care in producing the report even though it had not been retained by any one of them individually. That finding mattered later: it meant none of the three could be told the firm's obligations ran only to whichever of them had signed the original invoice.
4. Requested the working papers informally first, sending a joint letter from all three neighbours asking the firm to voluntarily produce the calculations, comparables and assumptions behind its number, to test whether litigation could be avoided entirely. Trying the informal route first was not just good faith toward the firm; it built the record of refusal a later court application would need to show the softer option had genuinely been exhausted.
5. Prepared and filed a court application naming the accounting firm as respondent once the informal request was refused, seeking an order compelling production of its working papers and setting out why they were relevant to the dispute among the co-owners and could not be obtained any other way, since none of the neighbours had independent access to the firm's internal file, and case law in this area places real weight on showing that softer, informal routes were tried and failed first.
6. Coordinated scheduling and cost-sharing among the three neighbours for the application, keeping the joint approach intact through the court process rather than letting it splinter into separate, competing filings that would have cost more and looked weaker to the court. A single, properly funded joint filing also meant no one of the three could later claim they had been outvoted or left to carry the expense alone.
7. Reviewed the working papers once produced with a valuation professional retained jointly by the three neighbours, identifying a specific calculation error in how improvements to one section of the land had been valued, which had understated the overall figure used to divide proceeds, and confirming that the same error did not affect any other section of the report the three of them had relied on.
8. Negotiated a revised split among the three owners based on the corrected figure, keeping the resolution within the group rather than turning the corrected valuation into a new round of litigation between them, and documenting the new split in a short written agreement so none of the three would later dispute what had been agreed. Settling it themselves, rather than asking a court to impose a division, kept the cost and the decision in the hands of the people who actually had to live with the outcome.

The outcome

The working papers, once produced under the motion, showed a genuine error: the firm had applied an outdated figure to a set of improvements on part of the land, which had the effect of understating the property's overall value and, with it, the size of the proceeds available to split. It was not a case of anyone acting improperly, simply a calculation that had gone wrong and gone unquestioned because none of the three neighbours had a way to check it. The valuation professional retained jointly by the group walked all three of them through exactly where the error sat in the file, so the correction was not something they were simply asked to accept on faith.

With the correct figure in hand, the three neighbours renegotiated the split of the original sale proceeds among themselves, adjusting the shares to reflect what the corrected valuation actually supported. The adjustment moved a meaningful sum, in the mid six figures, in favour of the co-owners whose shares had been understated, funded through a private settlement among the three of them rather than a further claim against the accounting firm. The firm itself was not pursued for the error once the working papers made clear it had been an honest miscalculation rather than a deliberate misstatement, and none of the three neighbours wanted a second, separate fight added to the one they had just resolved.

What made the result work was not only the legal step of compelling the working papers, but the earlier decision to keep Kasia, Agnieszka and Chamari pointed at the same target instead of at each other. A motion brought by two of the three against the third, or three separate and competing requests to the accounting firm, would likely have cost more, taken longer, and left at least one relationship damaged regardless of what the papers eventually showed. The three neighbours finished the dispute still on speaking terms, which was not guaranteed at the outset, and the corrected split closed out the land sale for good, with no further claims outstanding among any of them.

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