Technical due diligence before buying a multi-unit building

August 28, 2026 3 min read Greater Montreal

When you acquire an income property, the pro forma numbers rest on one assumption: that the building is in the condition you think it is. Technical due diligence is the step that verifies this assumption before it is too late. It turns guesses into data, and protects both your purchase price and your future return.

More than an inspection: a financial reading

Technical due diligence on a multi-unit building goes further than a residential inspection. It examines all the systems, structure, envelope, roof, mechanical, but above all it projects their future: remaining life of the major components, immediate and deferred deficiencies, and the order of magnitude of the costs to come.

On an income property, it is not today’s condition that matters most, it is tomorrow’s expenses.

What it changes for your transaction

A solid due diligence report gives you three levers:

  • Negotiate: documented deferred costs justify a price adjustment or upfront work.
  • Budget: you plan your capex instead of enduring it.
  • Decide: sometimes the best decision is to walk away, and it is better to know before signing.

Our analysis covers the technical condition and its financial impact, remaining life, deferred costs, effect on the asset’s value. It does not constitute an appraisal of market value (an act reserved for chartered appraisers, OEAQ); it complements it.

The risk of not doing it

Buying a multi-unit building without due diligence means accepting an unquantified risk. A roof to redo, masonry to repair, plumbing at the end of its life or a heating system to replace can represent tens of thousands of dollars, capex that, if not anticipated, directly eats into the return you thought you were buying.

An approach grounded in building science

Our work draws on building science and a financial reading of deficiencies: the condition of the components translated into figures your financial model understands, deferred expenses, impact on the return, negotiating arguments. The report is structured, prioritized, and designed for an investor’s decision-making.

500+ projects carried out on major sites in Quebec

Our approach

Boreon carries out technical due diligence for investors and managers across Greater Montreal, West Island, South Shore, Laval, North Shore. InterNACHI-certified inspectors, professional liability insurance, integrated thermography, and a schedule agreed in advance based on the size and complexity of the building. Our role: give you the information you need to decide, in your best interest.

Key takeaway

Technical due diligence verifies, before purchase, the assumption on which your entire pro forma rests. It reveals the costs to come, gives you negotiating leverage, and avoids nasty post-acquisition surprises. On an income property, it is the most profitable investment you will make before buying.

Considering acquiring a multi-unit building? Request technical due diligence from Boreon — the building’s condition, translated into a financial decision.

Get it inspected before you sign

Response within 24 business hours, no obligation.

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