What to Know Before Buying a Multi-Unit Building in Quebec

Buying a multi-unit building — a duplex, triplex, quadruplex, or larger plex — is one of the most popular real estate investments in Quebec. The province has a long-standing culture of plex ownership, and for good reason. When done right, an income property can generate monthly cash flow, build equity steadily, and create a long-term asset that appreciates in a market with strong rental demand.

But the purchase process is more complex than buying a single-family home. The numbers have to work, the legal framework has to be understood, and the building itself has to be evaluated with a completely different lens. At Murray Immeuble (murrayimmeuble.com), we guide buyers through every step — from identifying the right property to closing a purchase that makes financial sense from day one.

This guide covers what every prospective buyer of a multi-unit building in Quebec needs to know before signing anything.

Understanding the Quebec Plex Market

Quebec — and Montreal in particular — has one of the highest concentrations of plex-style buildings in North America. These properties were built in large numbers throughout the early and mid-twentieth century and remain a cornerstone of the city’s housing supply. Duplexes, triplexes, and quadruplexes make up a significant share of residential transactions in the province every year.

What makes Quebec’s plex market distinctive is the dual nature of these properties. They function simultaneously as a personal residence (if you choose to occupy one unit) and as an income-generating asset. This structure appeals to first-time buyers who want help covering their mortgage, as well as seasoned investors building a portfolio of revenue properties.

Demand in this segment has been consistently strong, and inventory — particularly for well-maintained plexes in established neighborhoods — is limited. Knowing how to evaluate a property quickly and make a credible offer matters as much as knowing what to look for.

The Financial Framework: How to Evaluate Whether the Numbers Work

The most common mistake buyers make when purchasing a multi-unit building in Quebec is falling in love with the location and the building before running the actual numbers. A property is only a good investment if the financial structure supports it.

Here is the basic framework to apply to any plex before making an offer.

Gross rental income. Add up all current rents across every unit. This is your gross revenue before any expenses. In Quebec, rents are regulated by the Tribunal administratif du logement (TAL), so rent increases are not automatic — understand what each unit is currently generating and what realistic upside exists over time.

Gross revenue multiplier (GRM). Divide the asking price by the annual gross rental income. A lower GRM indicates better value relative to income. In competitive urban markets like Montreal, GRMs have been rising, so benchmarking against comparable sales in the same neighborhood is essential.

Net operating income (NOI). Subtract operating expenses — property taxes, insurance, maintenance, vacancy allowance, and management costs if applicable — from the gross income. This gives you the true income the property generates before debt service.

Cash-on-cash return. Once you factor in your mortgage payments, what does the property actually put in your pocket each month? A positive cash flow is the baseline you should insist on. Negative cash flow deals can work in high-appreciation markets, but they carry more risk and require deeper reserves.

At Murray Immeuble, we walk every client through this analysis before they view a property, not after. Understanding the numbers in advance means you can recognize a good deal the moment it appears.

Quebec’s Legal Framework for Multi-Unit Buildings

Quebec’s legal environment for landlords and tenants is distinct from the rest of Canada. The province has some of the strongest tenant protections in the country, governed primarily by the Civil Code of Quebec and administered through the Tribunal administratif du logement.

Every buyer of a multi-unit property needs to understand the following before completing a purchase.

Lease transfers and eviction rules. In Quebec, a tenant’s lease does not automatically end when a building changes ownership. Leases follow the property. As a new owner, you inherit all existing tenants and their lease terms. If you intend to occupy a unit yourself or repossess it for a family member, specific legal procedures must be followed — and tenants have the right to contest repossession applications before the TAL.

Rent review and increases. Quebec’s TAL publishes annual guidelines for rent increases. Landlords are not prohibited from requesting higher increases, but tenants have the right to refuse and challenge any increase they consider excessive. Understanding the rent history of each unit is therefore critical during due diligence.

The seller’s declaration. Just as with residential properties, sellers of multi-unit buildings must disclose known defects through a seller’s declaration. Review this document with your agent and notary carefully. Undisclosed defects discovered after purchase can generate costly legal disputes.

Notarized transfer. All real estate transactions in Quebec must be completed before a notary. The notary conducts a title search, verifies there are no undischarged hypothecs or legal charges on the property, and ensures the deed of sale is legally valid. Budget notary fees into your total acquisition costs.

What to Inspect in a Multi-Unit Building

A thorough building inspection is non-negotiable when purchasing a plex. Multi-unit buildings carry maintenance complexity that a single-family home does not, and deferred maintenance in a rental property is almost always more expensive than it appears on the surface.

Prioritize the following during inspection:

The roof and exterior envelope. Flat roofs common on Montreal plexes have a finite lifespan. A roof nearing the end of its serviceable life is a significant capital expense — factor it into your negotiation.

Plumbing and electrical systems. Older plexes may have outdated knob-and-tube wiring or galvanized plumbing. Both create insurance complications and long-term reliability issues. Know what you are inheriting before you close.

Foundation and drainage. Water infiltration in basement units is a recurring problem in Quebec’s older building stock. Look for signs of historic flooding, efflorescence on foundation walls, and drainage patterns around the property.

Common areas and individual units. Inspect every unit if possible, not just the common spaces and one representative suite. The condition of tenant-occupied units varies widely and directly affects both your maintenance budget and your ability to attract quality tenants when units turn over.

Working with the Right Team

Buying a multi-unit building in Quebec is a team exercise. You need an agent who understands income property valuation, a notary experienced in commercial-residential transactions, a building inspector with plex-specific expertise, and ideally an accountant who can advise on the tax structure of your acquisition.

At Murray Immeuble (murrayimmeuble.com), we coordinate that process for our clients. We bring the right professionals together, make sure the due diligence is thorough, and ensure the transaction is structured correctly from a legal and financial standpoint.

Once you own the property, the work is just beginning. Our affiliate Frédéric Murray Management (fredericmurraymanagement.com) provides full-service property management for multi-unit building owners who want their investment handled professionally without managing it themselves. For buyers interested in larger multi-unit portfolios or commercial income properties, Murray Immeubles (murrayimmeubles.com) covers that expanded scope.

When you are ready to take the step into multi-unit ownership in Quebec, visit murrayimmeuble.com to connect with our team and start with a conversation built around your specific situation.