Treadstone Associates
Case File № 134 · Rental & Investment

Scaling past the comfortable number

a fourplex purchase and the portfolio-lender switch

A scaling investor's fifth financed rental — a Red Deer fourplex — ran into a mainstream lender's appetite limit on individually-financed properties, then failed TDS under a conservative add-back on the new building alone. A portfolio-specialist offset lender took TDS from 45.1% to 8.8%.

AlbertaUninsured · conventional purchaseFiled August 7, 20265 min read
45.1%

TDS on the new fourplex under Lender A's add-back — declined

8.8%

TDS on the same property under the portfolio lender's offset

5th

Financed rental property — past Lender A's individually-financed-property appetite

Anonymized illustration. The borrowers, dollar figures, and rates in this file are an illustrative composite — no real client is identifiable, and any rate shown is illustrative, not a quote. The rules are real: every regulatory figure is cited to its source in the Sources section, and the math computes exactly as shown.

№ 01

The client

An investor with four existing conventionally financed rentals in the Red Deer market wanted to add a fourplex — the fifth financed property — to the portfolio. Rental demand in the region, tracked in the same national vacancy data cited across this file, supported all four new units renting immediately.

Applicant

Existing 4-property investor

$8,700/month personal employment income

New purchase

$780,000 fourplex, Red Deer

All four units pre-leased at closing

Down payment

$195,000 — 25%

Conventional; structured for a four-unit investment purchase

New combined rent

$5,500/month

Across all four units

Existing debt

$460/month auto loan

Carried in both scenarios below

Existing portfolio

4 rentals, already financed

Cash-flow positive; excluded from the ratio test below

The new fourplex on its own, before either rental-income treatment is applied:

New purchase structuringAmount
Purchase price$780,000
Down payment (25%)−$195,000
Loan amount$585,000
Combined signed rent, four units$5,500/mo
№ 02

The problem

The first hurdle was not a ratio at all. Lender A's own appetite for individually-financed rental properties — each lender sets its own limit — meant a fifth financed property was already past what it was comfortable carrying for this borrower, regardless of the numbers. The second hurdle showed up once a lender willing to consider the file at all was found: a conservative add-back on the new, unseasoned fourplex.

The add-back arithmetic on the new property alone

  • Income used: $8,700 + $2,750 (half of the $5,500 combined rent) = $11,450/mo
  • Liabilities: $4,704 full carrying cost + $460 car loan = $5,164/mo
  • TDS on the new property alone: $5,164 ÷ $11,450 = 45.1% — over the 44% ceiling. Declined.

The existing four rentals were already cash-flow positive and were not the problem — the new, unseasoned fourplex, tested on a conservative add-back with no operating history yet, was.

№ 03

The numbers

The fourplex is tested on its own numbers: the borrower's existing portfolio is already comfortably covered and does not change under either treatment below.

Rate and payment on the new fourplexAmount
Contract rate — 5-year fixed conventional (illustrative, not a quote)5.24%
Minimum qualifying rate — greater of contract + 2% and 5.25%7.24%
Monthly P&I at the qualifying rate — the ratios run on this$4,184
Monthly P&I at the contract rate — what is actually paid$3,483

Full carrying cost on the new property

Carrying costMonthly
P&I at the qualifying rate$4,184
Property tax$520
Full carrying cost (heat is tenant-paid)$4,704

Lender A's 50% add-back on this new, unseasoned property is contrasted below with a portfolio-specialist lender's 80% offset, applied to the new fourplex alone.

TDS line (new property only)Lender A — 50% add-backPortfolio lender — 80% offset
Income used$11,450 (incl. half of rent)$8,700 (no rent added)
Full carrying cost / shortfall$4,704 (full)$304 (shortfall after offset)
Car loan$460$460
TDS45.1%  ✗8.8%  ✓

With $4,400 of the $5,500 combined rent offset directly against the $4,704 carrying cost, only a $304 shortfall reaches the liabilities — the mechanic behind why portfolio-specialist lenders can keep scaling an investor past the point where a per-file add-back cannot, as mapped generally in our comparison of rental income offset methods.

№ 04

The solution

A RECA-licensed Alberta mortgage broker moved the file to a lender that specializes in portfolio landlords: no headcount-style limit on individually financed properties, and an 80% offset treatment applied per property rather than a flat add-back, consistent with the underwriting approach set out in our rental-property underwriting guide. The existing four rentals were documented, not re-underwritten from scratch, since the portfolio lender's process nets each property's own numbers, and a rough cap rate check on the fourplex confirmed the purchase price was reasonable against its rent roll before the file was submitted.

The package focused entirely on proving the new fourplex on its own merits:

Signed leases for all four units at closing
Two years of T4s and NOAs for the applicant
Mortgage statements and lease documentation for the existing four rentals
Purchase agreement and municipal tax assessment for the new property
90-day history of the $195,000 down payment

The portfolio lender's underwriter needed to see that the new property could stand on its own once the offset was applied — and, separately, that the existing four properties were current and cash-flow positive, not that a single lender's ratio math could absorb the whole relationship at once.

№ 05

The outcome

Approved and funded: $585,000 conventional at 75% LTV, 25-year amortization, 5-year fixed term, becoming the investor's fifth financed rental property.

Alberta has no land transfer tax; Land Titles Office registration fees on the transfer and the mortgage were charged on a sliding scale and quoted by the lawyer as part of closing rather than itemized here.

№ 06

What to take from this file

  • 01A decline can be about appetite, not arithmetic. Lender A's limit on individually-financed rental properties was a policy ceiling, unrelated to whether the numbers actually worked.
  • 02A new, unseasoned property is judged more conservatively than a proven one. The existing four rentals were never the issue here — the fifth, with no operating history yet, was tested the hardest.
  • 03Portfolio-specialist lenders solve a problem mainstream add-back policy cannot. An 80% offset applied per property let this investor keep scaling past where a flat 50% add-back would stop them.
  • 04Test the new acquisition on its own numbers first. Isolating the fourplex's own TDS made the actual decision point — the rental-income treatment — visible instead of buried in a full portfolio recompute.

Sources

Every regulatory figure in this file traces to one of these primary sources. Client details and anything that varies by lender are illustrative, as flagged below.

Illustrative in this file — lender-specific, not rules:

  • 5.24% contract rate — rates move daily; not a quote.
  • Lender A's limit on individually-financed rental properties — each lender sets its own portfolio/exposure appetite; this is not a regulatory rule.
  • 25% down / conventional structuring — each lender sets its own down-payment requirement for a four-unit investment purchase.
  • 50% add-back / 80% offset treatments — each lender publishes its own rental-income policy.

Authority & provenance

How this case file was built

We publish the origin, the verification method and the reviewer for every case file, so you can judge how far to trust it before you rely on it with a client.

Where it comes from

Derived from files handled by Treadstone’s fulfillment desk and from scenarios contributed by partner brokerages. Names, employers, exact amounts and dates are changed so no client or file is identifiable.

Provenance: Composite — a pattern seen repeatedly on fulfilled files, not a single transaction.

What is verified

Every regulatory figure traces to a primary source listed above and was checked against it on the date shown. The arithmetic is recomputed by machine on every rebuild.

Anything that varies by lender is labelled illustrative rather than stated as a rule.

Who reviewed it

Reviewed for Canadian regulatory accuracy before publication, and re-checked whenever a cited rule changes.

Reviewed by: Nicholas Parson, Treadstone Associates — reviews every case file before publication.

First published 7 August 2026Rules last verified 7 August 2026Next scheduled review 7 February 2027

This case file is professional reference material for licensed mortgage professionals. It is not advice to a borrower, and it is not a lender commitment. Insurer rules, qualifying rates and provincial taxes change — confirm the current position with the insurer, regulator or lender before you rely on any figure here in a live file.

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Files like this are daily work for our desk.

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