These are just a few: wrinkle-resistant sheets (microfiber are the cheapest, most durable, and wrinkle-resistant)High-capacity automatic hand-soap and lotion dispensersrobot vacuumsShampoo, Conditioner, Body Wash dispensersShower curtains with snap-off liners

Either way, take down a sample board...clean and degloss it ...give it a light sanding....apply some wood conditioner (helps keep the stain even across the surface) and let it dry for 15 minutes or so.

They moved in with a broken washing machine that they set out on the back porch and left that behind along with a broken window air conditioner, a freezer they unplugged but left half filled with rotted meat, bags of mismatched shoes, broken furniture, childrens clothes, christmas ornaments, soggy bedding, rotting mattresses, more dirty diapers and, ironically, unused condoms.IF you can get a Section 8 tenant who can manage NOT to have a boyfriend/girlfriend/"fiance"/brother/sister/aunt/uncle/cousin/cousins children/babydaddy/babymomma/grandchildren come live with them because they've been evicted/kicked off someones couch/basement and have no place else to shack up you might have a chance to keep your rental unit in decent shape under this program. 

Change out the air filter on the air conditioner if it hasn't been.

I just had brand new electric furnaces and air conditioners installed along with ductwork, wiring, the whole 9 yards on a property that didn't have central heating/cooling before3 separate setups for 3 different units stacked on each other.

I hate to buy for appreciation only, as then every maintenance issue and catastrophic issue (Collapsed Sewer Line, Air Conditioner, etc.) has to come out from your own pocket and not the investment.

@Tom CamardaYou can get a portable air conditioner/heat pump that is rated for 400-500 square feet for $250:http://www.newegg.com/Product/Product.aspx?

I had an older house with little attic insulation and the air conditioner just could not keep up in a heat wave.

It turns out what I thought was baseboard hot water heating was actually just an old style of forced air vent so there was no need for new ductwork.In the process of installing the new air conditioner (there wasn't one before) I had to open up a wall and run a new circuit outside. 

Your electric bill is higher in the summer because you are using the air conditioner.