Twelve mistakes that destroy direct-property returns
The expensive errors are predictable: pricing by $/sq ft instead of cash flow; underestimating op-ex; no capex reserves; investing in unknown markets; bad tenant screening; over-leveraging; buying near the cycle peak; ignoring HOA dues; self-managing badly; emotional attachment; trying to time the bottom; and refusing to sell when conditions change.
Most beginner failures fall into a small set of repeatable mistakes. The most common: assuming a property's "price per square foot" makes it a deal when the cash flow doesn't work; missing 20–30% of true operating cost (because the seller's pro forma omitted it); under-reserving for the inevitable failure of roof / HVAC / water heater / plumbing.
The second cluster is about discipline: investing in markets you don't actually know; weak tenant screening (the wrong tenant costs 6–12 months of rent and damage); over-leveraging to 80% LTV that magnifies any downturn; buying at the cycle peak without margin of safety (2021–2022 buyers are still underwater on equity in many markets).
The third cluster is psychological: falling in love with the property (it's a business); trying to time the bottom (markets bottom only in retrospect); refusing to sell when conditions change ("inertia decides"). Annual review of every property: hold, sell, refinance? Don't let momentum substitute for analysis.