With the introduction of Bill 140 - Strong Communities Through Affordable Housing Act, one increasingly popular housing typology is secondary suites. However, their role within local housing markets has never been fully substantiated, numerically or functionally, Over the past decade, government agencies have employed a variety of techniques to estimate the number of secondary suites within local housing markets. However, due to a number of inherent limitations associated with available data sources and collection techniques, accurately estimated their prevalence is difficult because many secondary suites are not reported. As such, most data sources do not provide a complete estimate. In an effort to overcome these limitations, the following research paper has employed a methodological approach that combined MPAC data with visual surveys. The results of this approach will help provide a more accurate picture of the entire secondary suite rental market, identifying both reported and unreported units within Toronto.