From my research, I'm seeing $100-$150/sqft depending on complexity and material.

However, its subscription costs can add up, and the effectiveness of direct mail depends on execution and market conditions.

It also depends on your morality towards the people you rent to. 

How much will depend on how well their processes are designed.

For your agent to say you should not be concerned, again the answer is it depends.

Also, it depends on what area of the country you're talking about.

Going to depend much more on more details / your personal situation - all things equal you will probably get better rate/terms on conventional if you qualify for both

Then seller didn't have a clear marketable title and the ability to sell the property.So it really depends what the liens are.

Depends on the person, but as a professional real estate investor it would be a no brainer for me.

It depends on what the terms of your mortgage are.Pros-with no mortgage, you have higher cash flow.Cons-if you plan on buying more properties, you are better off saving the money for a down payment for your next place.The big questions are: can you get higher than 7% return if you invest that money elsewhere?