Key takeaways
- The expensive mistakes are operational, not acquisition.
- Most rookie failures trace to under-reserving and over-leveraging.
- Class C properties demand professional management to perform.
- Cap rate is not a return — it ignores debt and capex.
- Sentiment about 'the market' is not an underwriting input.
Core concepts
Underwriting errors
Using the seller's expense numbers, ignoring capex, modeling 0% vacancy, and treating last year as forecast.
Financing errors
Short balloon, adjustable rates without exit, and leverage that breaks at a 10% NOI decline.
Operational errors
No screening discipline, deferred maintenance, late rent that drifts to chronic.
Behavioral errors
Anchoring on purchase price, refusing to sell stale assets, chasing returns into unfamiliar markets.
Step-by-step framework
- 1Replace every seller-supplied operating number with verified actuals.
- 2Model vacancy at 8% minimum even in tight markets.
- 3Reserve 5% of gross rent for capex on top of repairs.
- 4Set DSCR floor at 1.25 and refuse deals below it.
- 5Quarterly review of every late-payment trend.
Common mistakes to avoid
- Believing the listing agent's pro forma.
- Self-managing a Class C property remotely.
- Refinancing into a higher payment 'because rates may rise.'
- Letting one tenant relationship drift past 60 days unpaid.
Frequently asked questions
Is cash flow or appreciation the bigger risk?
Negative cash flow kills you in 18 months; flat appreciation just costs opportunity. Cash flow first, always.
Is house hacking really risk-free?
It lowers entry risk but increases lifestyle risk — your home becomes leveraged business asset.
Should I buy in my own city?
Only if local yields meet your thresholds. Geography should follow returns, not the other way around.
How bad is one eviction?
Direct cost $3–6k; total cost with vacancy and repairs $8–15k. Screening prevents 80% of evictions.
Action checklist
- ☐Every operating number verified, not assumed.
- ☐Vacancy modeled at 8% minimum.
- ☐Capex reserve >= 5% of gross rent.
- ☐DSCR >= 1.25 at current rates.
- ☐No more than 30% portfolio concentration in one asset.
- ☐No deal pursued solely for tax benefits.
- ☐No financing chosen on rate alone — term matters more.