They are using arbitrary numbers when evaluating deals (vacancy 10%, maintenance 10%).

I've always been curious about a few markets, but I figured the vacancy might cause some issues.

Subtract off vacancy, maintenance, cap esp (at $122, jk).  

Factor in ALL expenses like property taxes, insurance, repairs, maintenance, vacancy rates, and potential property management fees.2.

escrow needs to allow draw down for your mortgage payment ( which means sale went through) less maybe 2 months for vacancy, plus a generous repair allowance.

I don't need it immediately but likely in case of emergencies or vacancies. 

No I have not been in person, and what you are describing is exactly what I'm worried about.I will say that I do have a contractor who I trust to do an honest thorough inspection (I requested several references who all gave positive feedback, and the one property I did ask him to inspect he found a major structural issue and immediately told me not to considering buying it).It seems like when most people run into trouble its because their estimates of vacancy, maintenance, capex were all too optimistic.

If that's your goal, I applaud you, but I'm sure most would choose other avenues for their charitable contributions.I like the idea of "organic vacancy". 

Monthly cashflow does not account for vacancy, repair, cap ex.

Those markets dealing with 10+ caps are usually pretty rough areas and you get needy tenants, higher Vacancy, higher maintenance costs and turnover expenses.