Who writes these guides
Mathis Desgagné builds and runs Dewin as a sole proprietorship. Dewin began with a real rental portfolio and a practical problem: finding a clearer way to analyse a purchase, work through the due diligence, and follow the money after closing.
The guides on this site come out of that work. They explain the calculations Dewin performs — effective gross income, operating expenses, net operating income, debt service and the ratios built on them — using the same formulas the product uses, so a reader can check the arithmetic by hand.
What this is based on
- Owning and operating Canadian rental property, which is where the examples and the edge cases come from.
- Building Dewin's financial engine: the formulas in these guides are the ones the software runs, documented and reproducible.
- Working through CMHC financing, including MLI Select, conventional mortgages and the difference between a loan capped by value and one capped by income.
How these guides are written
- Drafting is done with AI assistance. The structure, the worked examples and the wording go through automated tools before a human reads them.
- Nothing is published without review. Mathis Desgagné reads each guide before it goes live and answers for what it says — the name on the page is the person you write to when a number is wrong.
- The numbers are checked against the same engine the product runs. When a guide states that a $790,000 balance renewed at 6% over 20 years costs about $68,000 a year, that figure is recomputed, not estimated.
- No return is ever promised. A guide explains a calculation; it does not tell anyone what a building will earn.