Screen as best you can and realize that stuff happens and you can't always get it right.The numbers are really important.

Open windows, check screens.

Do a really good job screening a tenant and manage it yourself, at that point you will probably be cash flow neutral.

Account Closed,Student rentals can have above average cashflow as long as you screen your tenants really well.

So it could be more screening work on the front end, but that too could help you retain tenants.There is a good book on this called "Investing Duplexes, Triplexes and Quads" by Larry Loftis.

They kind of give up expecting professionalism, same day call backs, transparent booking, thorough tenant screening, fast and economical repairs, etc. and just hope for someone that doesn't rip them off.

Build a lattice screen outside that clear the top of the unit, leave plenty of breathing space, a couple feet so you can get in there to clean it too.

There is also electronic rent payments through Dwolla and Paypal.I want to say that they make their money through tenant screenings but I have not looked into this aspect. 

Assuming the house isn't built on a hill and is sliding, this type of slab cracking is very common in my area where oil companies have sucked the blood out of the earth for over 100 years.

Jean is right, you need a little landscaping, new light fixture and maybe a screen door.