Can try to reposition to Class B, but neighborhood may impede these efforts.Vacancy Est: Historically 10%, but 15-20% should be used to also cover tenant nonpayment, eviction costs & damages.Tenant Pool: majority will have FICO scores of 560-620 (approaching 22% probability of default), many blemishes, but should have no evictions in last 2 years.

I’m 18 and currently living at home with low expenses.My dilemma: Should I buy a duplex as a house hack and cover the negative cash flow to start building equity?

Set aside a big pile of cash or rely on a line of credit you won't be using.The oversimplified insurance concept is to pay a small premium to cover a large loss.

I think @Paul Sandhu captured the list of skills you need to find, and that you can probably find someone with "3M Talent" (or at least "2M Talent" to cover several areas.)

in cash flow would cut it for me. i'd want enough to cover the mtg, but also R&M and a little for vacancy. if i can't do that plus have a little actual "cash flow" left over.... i'm still here :) if that's any indication. 

This sounds risky, are you being compensated by additional rent and have you checked with your insurance to ensure you are covered. 

As for non-bank loans, I'm familiar with a loan program that provides 100% financing, but it requires a minimum 650 credit score and proof of funds covering 12 months of interest.

Insurance would cover it, I would pay the deductible, and no assets would be lost.If you are in an area like San Diego where people are more likely to sue, a judge is more likely to find you guilty, and the payout is expected to be higher, you may consider an umbrella insurance policy.

Can try to reposition to Class B, but neighborhood may impede these efforts.Vacancy Est: Historically 10%, but 15-20% should be used to also cover tenant nonpayment, eviction costs & damages.Tenant Pool: majority will have FICO scores of 560-620 (approaching 22% probability of default), many blemishes, but should have no evictions in last 2 years.

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