I could be wrong, but I think I can use the equity I've built up with this house to cover the 20% for the conventional mortgage and avoid PMI.

First, I'm not trying to say that anyone is wrong in what they have said.

If you are worried about vacancy, you are probably investing in the wrong area.

I have also done deals above 80% and lost money, but the initial analysis did not have them at above 80% of course, things went wrong and as such, the % of the ARV was hurt in those cases.

Nothing wrong doing that in the beginning or from time to time. 

I guess I was Googling the wrong phrases

Don't think there is anything wrong with doing it from your personal, I would just keep the Personal and the real estate biz separate.  

If Im wrong here please advise.A factor that seems to matter as I see it is the equity in the property. 

The bank is less likely to foreclose on a property that has so little equity.Correct me if I am wrong, but as long as an invest property is full occupied and has consistent cashflow, a higher rate should not be considered an obstacle because the tenants are paying for the mortgage.

There's nothing wrong with considering the experience of others in your decision making.