What is a rental market survey?
A rental market survey (or rent comp study) is a structured comparison of the asking rents of buildings comparable to yours. It answers one question: for this unit type, in this location, what is the market asking right now?
It doesn’t replace a certified appraisal, and it doesn’t set a rent on its own. It gives a rent decision a factual, dated and verifiable basis.
When do you need one?
- When re-leasing a vacant unit, to set a rent that’s neither too high (long vacancy) nor too low (lost income).
- Before a renovation, to estimate the achievable rent afterwards.
- When acquiring a multifamily building, to test the seller’s income assumptions.
- For financing or refinancing, when a lender asks you to support projected rents.
- For an annual portfolio review, to see where each building sits against its market.
The 6 steps of a rental market survey
1. Define your building (the “subject”)
For each unit type, record the label (in Québec: 3½, 4½, 5½…), size if known, floor, inclusions (heat, hot water, appliances, parking) and the current or target rent. Without a precise starting point, comparisons drift.
2. Choose comparables
Pick buildings that would attract the same tenants: same area, same unit type, similar construction era and finish level. Aim for at least three current comparables per unit type; below that, the observed gap says little.
3. Record asking rents with their source and date
For each comparable, record the asking rent, the page where you saw it and the date. Also note what the price represents: one exact unit, a “from” price or a range. “From $1,395” is not the rent of a specific unit.
4. Normalize inclusions
Two rents only compare if their inclusions do. A heated unit and an unheated one don’t sit in the same price bracket. When information is missing, leave it “unknown” rather than guessing.
5. Interpret the gaps
Place your rent within the range of current comparables rather than relying on a single average. Drop withdrawn offers and stale observations: a price seen three months ago may no longer exist.
6. Document it in a dated report
Keep the list of selected and excluded comparables, with the reason for each exclusion, the sources and the dates. When you redo the exercise, create a new version instead of overwriting the last one — that’s what makes your decision defensible to a board, lender or client.
Criteria for choosing a comparable
| Criterion | Why it matters | Good practice |
|---|---|---|
| Distance | Tenants compare buildings in the same area. | Start within 1 km, widen if needed, and record the radius used. |
| Unit type | A one-bedroom and a three-bedroom serve different needs. | Compare type by type. |
| Era and finish | New construction often commands a premium. | Group buildings of similar era and finish level. |
| Inclusions | Heat or parking changes the real price. | Record every inclusion; leave “unknown” when not stated. |
| Freshness | Offers disappear quickly. | Favour recently seen offers and date each one. |
Common mistakes
- Comparing an asking rent with a CMHC average rent. CMHC measures rents of occupied units; advertised rents can differ from them significantly. Both are useful, but they’re not interchangeable.
- Treating a “from” price as an exact rent.
- Counting the same listing several times across sites or dates.
- Keeping withdrawn offers in the average.
- Not dating the survey, which makes it impossible to defend six months later.
Market surveys and rent-increase rules
A market survey helps price a unit being re-leased or value a building. It doesn’t determine the allowable increase on an existing lease: in Québec, that follows the rules of the Tribunal administratif du logement (TAL), which are not based on market rents. Other provinces have their own rules.
Go further: our methodology and the rental glossary.