Expenses that buyers commonly underestimate include a maintenance reserve, property management if you are not self-managing, and vacancy between tenants, all of which reduce net operating income below the gross rent figure most listings advertise.
A single-family rental and a purpose-built rental unit carry different risk profiles even at an identical calculated cap rate, since a single-family property depends on one tenant for all of its income while a multi-unit property spreads that risk across several.
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