The Old Lease Addendum That Decided How Much Was Actually Owed

The situation

The letter arrived in a plain envelope, forwarded from an address Niloufar barely remembered: a note from a transit authority's human resources office, asking whether Giulia could be reached at her old address for a records request tied to an unrelated pension matter. Niloufar had never heard the name before, but the letter mentioned, almost as an afterthought, that Giulia had once managed the rental unit above the clinic for the building's previous owner, years before Niloufar bought it, a detail that would turn out to matter far more than the pension request itself.

Niloufar owned a small dental clinic in Cobourg, purchased four years earlier from a retiring dentist who had also owned the building outright, including a self-contained apartment above the clinic. Niloufar had continued renting that apartment to its existing occupant, Parisa, a dental assistant who worked for the previous owner and stayed on with Niloufar's practice after the sale. The arrangement had run smoothly for years, with Parisa paying rent directly and working her regular hours at the clinic as two entirely separate matters, and Niloufar liked it precisely because it stayed simple.

Roughly a year before the letter arrived, Parisa's rent payments became irregular, then stopped almost entirely. Niloufar, uncomfortable pressing an employee she worked alongside daily, let the arrears accumulate longer than she should have, tracking what she believed was owed based on the rent figure quoted to her informally, in passing, by the retiring dentist during the handover of the building rather than anything written down at the time. By the time she decided she needed to act, the two sides disagreed sharply on the number: Parisa insisted she had been paying an amount fixed years earlier under an addendum signed with the previous owner, one that predated a rent increase Niloufar believed had been agreed to but could not locate any signed record of.

Without a document settling which rent figure actually governed the tenancy, Niloufar could not confidently calculate the arrears, could not file anything at the Landlord and Tenant Board with numbers she could stand behind, and risked either overstating what Parisa owed, straining a relationship that mattered to her clinic's daily operations, or writing off money that was genuinely due to a practice that, like most small clinics, could not easily absorb an unplanned shortfall.

What the documents showed

The apartment's rent history turned out to run through a chain of documents that had not travelled cleanly from the previous owner to Niloufar when the building sold. The original lease, several years old, set an initial rent. A later addendum, signed between the previous owner and Parisa, adjusted that rent upward, but the copy in Niloufar's purchase file was unsigned, a draft that had apparently been superseded before closing without anyone updating the paperwork she received, a gap that a routine due diligence review might have caught but did not.

The signed version of that addendum, it turned out, had been kept not by Parisa and not in the clinic's own records, but by Giulia, who had managed the building's rental unit as a side arrangement for the previous owner before Niloufar's purchase and had since left the role entirely, moving into an unrelated career as a transit operator. Giulia had kept a personal file of the properties she had once managed, a habit left over from her old work, and the signed addendum with Parisa's actual agreed rent was tucked in that file among records for several other small rental properties.

Under Ontario's residential tenancy rules, a rent increase is only valid if it followed the required notice and stayed within the annual guideline, or was properly approved by the Board where the guideline did not apply; a signed document alone does not automatically make an increase enforceable if those requirements were not met. Checking that the addendum's increase had been given on proper notice and fell within the guideline rate then in effect mattered as much as finding the document itself, since neither a court nor the Board treats an improperly implemented increase as binding no matter how clearly both parties appeared to agree to it in writing. Once confirmed, the rent legally owing was the amount properly established through that documented history, not simply the figure either side believed was correct.

Locating Giulia and obtaining a copy of the signed addendum resolved the core factual dispute: Parisa's rent had, in fact, been validly increased years earlier, and her payments had fallen behind that correct, higher figure, not the lower one she had assumed still applied. The gap between the number Parisa believed she owed and the number actually owed was significant, in the mid five figures once the accurate rent was applied across the full period of missed and partial payments, and confirming it properly was the difference between an application built on solid ground and one vulnerable to being picked apart at a hearing.

What we did

1. Reviewed the full documentary record Niloufar had from the building purchase, identifying that the addendum in her closing file was an unsigned draft rather than an executed document, which explained why the rent figure she had relied on, quoted informally at the time of purchase, did not match Parisa's own understanding of what she owed under the terms she believed still applied.
2. Traced the addendum's origin back to the previous owner's rental arrangement, establishing that a separate individual, not the previous owner directly, had handled the day-to-day management of the apartment and was the more likely holder of any signed original, since the previous owner's own records, reviewed with his cooperation, contained nothing beyond the same unsigned draft already in Niloufar's file.
3. Located Giulia through the transit authority correspondence that had prompted the discovery, confirming her new occupation and current contact details, and reached out directly to explain the records request without implying any obligation on her part beyond a favour connected to a relationship she likely still valued from her time managing the property, which made the outreach considerably easier than a cold request would have been.
4. Obtained a copy of the signed addendum from Giulia's personal files and verified its authenticity against the signatures and dates on the other tenancy documents already in hand, satisfying ourselves it would hold up as reliable evidence before relying on it in any filing, and confirming with Giulia directly, by way of a short signed statement, how the document had come into her possession.
5. Confirmed the increase itself had been properly implemented, checking that the addendum's effective date and amount fell within the annual guideline rate that applied at the time and that proper written notice had been given, since an increase agreed to on paper is not enforceable if it skipped those statutory steps, and we did not want to build an arrears figure on an increase that could later be challenged as invalid regardless of the signature on it.
6. Recalculated the arrears from the correct, documented rent figure, applying it across the full period of missed and partial payments to produce a defensible total that accounted for every payment Parisa had actually made along the way, cross-checked against her own bank records so the final figure could not credibly be disputed on the numbers by either side once the calculation was laid out in full.
7. Prepared and filed the arrears application with the Landlord and Tenant Board, attaching the addendum and a clear payment history so the Board could see exactly how the figure had been reached, reducing the chance of the application being challenged on the numbers themselves, since the Board could trace every dollar in the arrears calculation back to a specific, dated source document.
8. Proposed a repayment schedule to Parisa's advocate before the hearing, recognizing that Niloufar's priority was recovering the arrears and preserving a working relationship with an employee she valued, not ending the tenancy, and structured a proposal realistic against Parisa's income as a dental assistant, spreading the arrears over a period long enough that the monthly amount would not itself become unaffordable and restart the same problem.
9. Presented the agreed schedule to the Board for approval, walking through the documentary basis for the arrears figure so the order reflected a number both sides, and the Board, could rely on without further dispute, and so the schedule itself would stand as a clear, enforceable reference if a payment were ever missed later, rather than something either side could later claim was never truly settled.

The outcome

The Board approved the repayment schedule largely as proposed, built on the arrears figure the addendum had established. Parisa agreed to a fixed monthly repayment amount on top of her ongoing rent, calculated to clear the arrears over a defined period without requiring a lump sum she could not have produced, and the schedule was filed as a formal Board order rather than an informal handshake.

The tenancy continued, and so did Parisa's employment at the clinic, which had been Niloufar's preference throughout: she wanted the money owed resolved cleanly, not the working relationship damaged. The clear documentary basis for the arrears figure meant neither side spent a hearing arguing over numbers that a signed document could settle in minutes once it was found, sparing Niloufar the outcome she had most wanted to avoid: a contested hearing with her own employee across the table disputing figures.

The case turned entirely on a document that neither party to the dispute had ever controlled. Without tracking down Giulia and her personal files from a role she had left behind, Niloufar would have been filing an arrears application built on an unsigned draft, vulnerable to exactly the kind of challenge that draws out a hearing. It also mattered that the increase itself had been properly implemented; a signed document recovered years later is only useful if the increase it records was valid, and confirming that meant Niloufar never had to defend the figure on two fronts at once, its existence and its legality, in front of the Board.

Niloufar now keeps a simple, updated file of every tenancy document connected to the building, with copies stored separately from the clinic's operating records. She also checks in with tenants periodically to confirm their understanding of the current rent in writing, a small habit that would have surfaced the discrepancy with Parisa long before it grew into a dispute serious enough to need a lawyer and a Board application to sort out.

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