When the tenant left we had to wash all the walls and then paint in some cases with stain blocker to avoid it showing thru.

If it's an owner occupied property, they have to pay to live somewhere, so the PITI and normal monthly costs are likely the same as what they'd pay else where, so to me that's a wash. 

County recording fees, Lawyer fees for deed prep, Washing hands fees, fees for Washing your hands before prepping your hands you get it.  

Boy, was he pissed off!

Was he qualified to make such repairs?

@Brian Burke That was my assumption too, it's a wash until you get to more than 3 floors.

just to be clear, are you thinking to put washing machine in 4 plex or 8 plex? 

I need to figure out how to stop this mildew or algae stuff that shows up on one of my rental house's older vinyl siding.I end up having to pressure-wash this crud off at least yearly, but it really needs it 2-3 times per year!

If it is several rooms and they need washing I usually get a helper to wash and clean while I paint and to remove tape before paint dries, clean up paper or plastic etc. 

Find the investors in your area who are, well, still solvent, learn from them, learn from others who are successful.