When you do a little extra work ahead of time, the process goes so much more smoothly.

They offer invaluable insights into neighborhoods, regulations, tenant demographics, and market conditions—information you can't get from books or podcasts.The good news is that working with an investment team typically comes at no extra cost.

I invoiced an extra 25 dollars for part of the cleaning that I needed done extra and it was disregarded.

If so how difficult is that?

I've tried the lower 6-7% PMs and usually you'll either pay mark ups on repairs (what you've noted) or pay extra fees (i.e. labor hours, extra calls) that you may or may not notice. 

You'll likely pull a few hundred extra dollars and will will get shorter leases that could work better for your traveling.

I suspect you will learn the difficulties of student and rent by room models.  

Helps with your debt to income, better opportunities at cash flow, and typically requires less down to purchase.In regards to challenges, I usually build in an extra 10-15% to deal with things that I can't see behind the walls, including dry rot, electrical or plumbing issues, etc.

It tends to hide marks better.Walls: Neutral tones like SW Repose Gray, Behr Swiss Coffee, or Moore Classic Gray are renter-friendly and modern.Trim and Doors: Use a crisp white like SW Extra White or Moore Chantilly Lace.Accent Walls: For a touch of style, consider an accent wall in soft blue-gray. 

I'd hate for a temporary dip in the quality of the tenant pool to be giving my landlord "spidey sense" false alarms on account of taking an extra month or two to fill a unit.