Due Diligence: The Documents a Serious Buyer Requires for Your Plex

ImmoMulti — a direct buyer of income properties on the North Shore — sees it in every transaction: a plex sells on paper first. Before signing, every serious buyer runs due diligence, a methodical verification of the leases, the numbers and the condition of the building. The seller who hands over a complete file at offer stage shortens the conditions period, cuts the risk of renegotiation, and projects the image of a well-managed property. This guide, from the owner-seller's point of view, walks through the eight blocks of documents you will be asked for on your plex or multiplex — and how to gather them ahead of time.

What is due diligence when selling a plex?

Due diligence is the period during which the buyer verifies the leases, financial statements, taxes, physical condition and title of the property before removing conditions. It is framed by the purchase promise. A seller who provides a complete document file speeds up this stage and secures the transaction.

When a buyer submits a purchase promise on an income property, it is almost always conditional on their satisfaction with various documents and verifications: review of the leases, financial analysis, inspection, financing, title verification. That is due diligence. During this period, the buyer seeks to confirm that the building is worth the price offered and hides no surprises.

The seller's role is not passive. According to the OACIQ, the seller must provide the broker with available documents supporting their answers — notably invoices, warranties, plans, estimates, permits, reports, notices and leases. The more complete your file is from the start, the fewer reasons the buyer has to delay, renegotiate, or walk away.

Source: OACIQ — Guideline "Verification, information and advice" (duty to inform).

What financial and rental documents must you provide for a plex?

The leases in effect, the rent roll and the financial statements (rental revenues and operating expenses) are the heart of a plex file. The OACIQ indicates that, for an income property, the seller must provide the leases and documents related to the rental units in order to establish the revenues and expenses of the property.

The buyer of a multiplex is first paying for an income stream. Three documents let them validate it:

• The leases in effect — one signed copy per unit, including schedules, rent-modification notices and any special agreements. The OACIQ confirms that copies of the leases in effect must be provided for an income property.
• The rent roll — a summary table showing, unit by unit, the current rent, the lease start and expiry dates, the services included (heating, parking, appliances), arrears and any deposits. It is the tool that lets the buyer calculate the real gross income of your plex.
• The financial statements (revenues and expenses) — the detail of rental revenues collected and operating expenses (taxes, insurance, energy, maintenance, management) over the past two or three years. These figures feed the calculation of net operating income, GRM and cap rate.

A rent roll that is clear and consistent with the leases is probably the most scrutinized document. The slightest gap between the rent stated on a lease and the one in the table forces the buyer to dig — and to doubt.

To turn these figures into a building value, our guide to multiplex yield calculation explains the GRM and cap-rate mechanics the buyer applies to your file.

Why provide the tax bills and energy invoices?

The municipal and school tax bills, along with the energy invoices (electricity, gas, oil), let the buyer reconstruct the real operating expenses of the plex. These are third-party-verifiable cost items that lend credibility to your entire financial picture.

The municipal and school tax bills are unavoidable: they are often the two largest fixed expenses of a plex on the North Shore, especially after recent property reassessments. The buyer compares them to the amount stated in your financials. Providing the assessment notices for the past few years removes any dispute on this item.

The energy invoices — electricity, natural gas, oil, depending on the heating system — clarify who pays for what. In a building where the owner covers heating for common areas or certain units, these invoices document an expense the buyer will have to assume. They also help flag an energy-hungry building, a common negotiating point.

The location certificate, renovation history and permits

The Chambre des notaires recommends an up-to-date location certificate less than 10 years old, provided by the seller. To this add the history of major work and the corresponding municipal permits, which prove the condition and compliance of the building.

The location certificate is the document that describes the current condition of the property: it contains the plan of the property and the surveyor's report. The Chambre des notaires du Québec recommends that an up-to-date certificate describing the current condition of the property and dating no more than ten years be provided to the buyer by the seller.

The history of major work — roof, windows, plumbing, electrical, heating, foundation — reassures the buyer about the real condition of your plex. Keep the invoices, warranties and reports. The corresponding municipal permits prove these renovations were done by the book; their absence raises a doubt about compliance and can drag the price down. The OACIQ, for its part, lists invoices, warranties, plans, estimates, permits and reports among the documents to be provided in support of the seller's declarations.

For the physical condition of the building, our guide to the pre-sale inspection of a plex rounds out this documentary side.

Source: Chambre des notaires du Québec — "Do I need a new location certificate?".

Insurance policies and title verification by the notary

The building's insurance policies document the actual coverage and premiums. On the title side, the Chambre des notaires explains that the notary ensures the seller is the true owner and guarantees a clear title — based notably on an authentic copy of the title and the location certificate.

The insurance policies in effect show the buyer the current coverage and the real level of premiums — an expense item that has risen sharply in recent years for income properties on the North Shore. Providing the policy and the claims history avoids unpleasant surprises at renewal and lends credibility to your financial statements.

Finally, title verification falls to the notary. The Chambre des notaires du Québec explains that, in carrying out these verifications, the notary ensures that the seller is the true owner of the property and guarantees you a clear title of ownership. The seller must provide an authentic copy of their title and the location certificate. By gathering these documents early, you let the notary begin their searches without waiting.

Source: Chambre des notaires du Québec — "What does a title search by a notary involve?".

How do you prepare a complete file to sell your plex faster?

Gather the eight blocks of documents before listing, organize them in a single file (digital, ideally), and hand them over as soon as the offer is accepted. A complete file shortens the due-diligence period, limits renegotiations and signals a well-managed property.

The logic is simple: every missing document is a reason for the buyer to extend their conditions or lower their price. Conversely, a seller who provides a complete file as soon as the offer is accepted moves financing, inspection and title verification forward in parallel — and closes the transaction faster. This is even truer in the North Shore plex market, where savvy buyers compare several buildings at once.

Note that this file of supporting documents should not be confused with the seller's declaration about the immovable, a separate OACIQ form in which you answer questions about the condition of the property. The due-diligence file gathers the documents that back up those declarations. For particular situations — succession, corporation, lease assignment, complex titles — consult a notary or tax specialist.

For the rest of the selling journey, see also our North Shore real estate market analysis, which places this documentary file within the broader process.

Informational content only. Does not constitute legal or tax advice. Requirements and deadlines may change; consult a notary or tax specialist for advice specific to your property and situation.