ROI would all depend on how good of deal you find and your investment strategy.

The going rate locally ranges from $1600-2100/mo, depending on time of year and if I choose to allow pets.

It seems like the returns and characteristics are very zipcode/neighborhood dependent so I'd recommend you talk to people and do research before buying.

Whether this income would qualify you or not would largely depend on how much you claim on your taxes and for how many years. 

Depending on who you get in your network, will your cleaner let you know of the damage that should be charged to the previous tenant? 

It is often more expensive, and can be difficult to find qualified tenants, depending on your market, but legally speaking, it isn’t any more complicated than other states.

Would depend on the lender.

This will increase your filing fees significantly versus just your normal personal return Depending on the level of personal services provided during the tenants stay you will report it as self employment income versus passive income.  

Absolutely doable depending on a state you are buying. 

@Dan Cantelmo Need more info and it depends on the current value.