STR loans qualify similar to LTR, and with the usually higher monthly rents from STRs, the lender can leverage higher loan amounts. 

Will you get the extra rent for the additional bathroom and how long will it take to recoup the cost?

You can usually stretch it another 3-5 years with some selective repairs.

If they are reasonable, there shouldn't be an issue.I would advise to add a clause to your lease about extra people living in the apartment.

Typically, when I'm counseling with an out of state client that is living in a higher cost of living area - the client is usually better off to house hack in an expensive market rather than buying RE in a lower cost of living area unless there is a lot of excess capital to work with.If you have any questions - feel free to reach out as I am happy to chat.

What pro-rated items do you usually pay for?

If you are working in the HOA and spending time that is integral to the earning of monies for the rental properties, these extra hours managing managers, educational hours, reviewing financials etc should count.

Goosehead usually is good with it

@Huggy Ford Bigger Pockets can be a helpful site but admittedly, we are usually only talking about residential stuff. 

i usually give around 10 leads for them per month. from that 10, 6-8 closing a month from me alone.