Thermostats, thermocouples, the common furnace control board, furnace filters.

We have three relatives visit us every year and I can see a substantial increase in our water and sewage bill even thought they only stay with use for a week or two due to the extra baths, cooking and toilet use.Washing cars or neighbors stealing water from a faucet can also be a problem in certain areas.If you can find a good time to check then check the meter on the street, make sure there is no water running in the unit and that no one will turn on or flush anything at all, let it sit 30 minutes or so and see if the meter goes up which would indicate a leak somewhere.The tenant may also be able to call the water company and plead their case (Not blaming you) that there was a leak that was out of their control and that they didn't realize it soon enough and see if they will give them a break on the bill, it depends on the water company but I have seen the water companies in my area give a break on the bill for certain circumstances.

Before this short discussion spins too much further out of control, I would like to point out that I'm not advertising to God and everybody in my target zip codes. 

Find the deals(by marketing) and you control what you can do with the deals.

With PPC, you can't do it well unless you pay someone and you're not in control of what you are doing.

Others will have real-world problems beyond their control like a death or loss of job.

You get great yields and better control over your money, and should you have to foreclose, you are safe as long as you gave yourself enough equity, etc.

Person doing the arbitrage has little control of property and that is why I recommend people don't do it.

We provide quality services at a fair price and use mostly in house labor for all of our work guaranteeing quality control and a quick response.We offer snow removal, snow plowing, shoveling, and salt/de icing for both residential and commercial applications. 

The latter will give you move control and make sure it is being done.