Getting the tenant out via OMI is possible but it depends on the tenants situation like I mentioned above.

However, a lot of those answers are going to be dependent on where you're looking to invest. 

I am estimating that with loan payments and management fees, this would net $10,000 to $18,000 annually, depending on vacancy and management fees.

I think it's 4 or 6+ units, so it depends on what you are buying.

Depending on town regulations, most all have it outlined in their contract verbiage that the septic tank is to by pumped, collapsed and buried.This was truthfully a small expense in the grand scheme.

Changing your policy mid term isn't always difficult just depends on the Carrier's cancellation policy.  

Like mentioned it can depend on goals a lot.

However, if it's still the best deal around, and doesn't need any work, and you can find great financing, and and and....Also, it depends on the cost of utilities in your area.  

In regards to question #2, really depends on your credit, experience, income and liquidity.

Depends on how big of an area and how serious the issue is.