Typically a control panel will have to be replaced every now and then, sometimes a seal leaks and needs a new gasket, etc.. things happen, the filter needs to be swapped out periodically.  

It's not something that needs to but done now but I was told the quality of the pipe used it's only a matter of time before I get a leak or it fails so I'm just going to replace it sooner rather than later so I don't get a call from a tenant at 2 o'clock in the morning. ..

Leaks still prevalent in pipes and refusing to fix them, contractors worker and his family squatting in my home without my permission, and lazy work done to finishes of the home.

I had a water line leak and the plumber came out same day but there was still a 2 day wait until they could fix it since the utilities had to be flagged by the city before they could dig so others have said this is a slow process and there was plenty of time to contact you. 

A few things i captured are - major items like roof, furnace, AC unit, do the lights work, faucet running, water heater, the grade around the house, any water leaks in the roof, insulation in the attic? 

Once you get in the game and run what's it's really like to do real estate (leaking faucets, showing units, deal sourcing etc) you'll have much more confidence about doing it for yourself.Hope this info is helpful!

look for clean walls, clean trim, siding, appliance/HVAC age and condition, turn on the water, check for leaks.

What happens when your tenants does not report a leak and your pipes break.

Just spent $1600 to replace a  Leaking coil on a less than 5 year old AC.

Some will last a long time, like tuck pointing a chimney (hopefully 50+ yrs) but is also pretty pricey to do when it does come up (and you typically find out you need it because you are getting a leak that took out drywall and insulation).