The worst situation to be in is a cash-strapped, stressed out house hacker without the funds to repair/maintain an old home, especially if something bad happens (say the roof develops a leak and you need to shell out 10 to 15 grand for a new roof). 

Basement has leaks everywhere(many properties in Chicago do) and some minor other problems.

One tenant complained about water leaking.

Am afraid your lease was not descriptive enough and may have a tough time in court.Take this as a lessons learned and start working on improving your lease from the things you are seeing with current tenants and then wait it out if you can, which you seem to indicate you can do.Even with a very tight lease, I paid close to $3000 in evictions not to mention the heartache from tenants that I inherited on my first duplex purchase where I lived on one side and rented the other.I will never again inherit tenants.These ones moved in an extra person a year and a half in, despite lease saying not to, smoked marijuana and cigarettes in house despite lease saying not to and worse, I lived on property so they became very sneaky about how they broke their lease and these was just a nightmare.I hate evictions, but I equally hate bad tenants and tenants that I have not personally screened and that is why I refuse to take on tenants at property purchase.I also always, always do unit inspections.I just did one yesterday and glad I did, which I had initially decided I would not do, but nope, get in there and see how your property is being maintained.My fairly new tenant seems to have an issue with basic housekeeping.There was a smell in the unit, which I still cannot figure out what it is, but brought it to their attention and will be following up, he has a car that leaks oil endlessly on my newly resurfaced concrete driveway and garage flow, has a ring in toilet bowl that is also stained and smelling toilet from lack of cleaning.It pains me to see a unit that I took great care of when I lived in it to see what it is quickly turning into but I am nipping that in the butt right now.Dirty tenants can be a liability to any landlord, but overall tenants will try to test you and see just how vigilant you are and how much they can get away with.I also make notes on what I want to update on my next lease when I run into issues.Pets?

This will let you know if there are any plumbing leaks or any clogs in the sewer lines.2nd look at the foundation very closely, look for any stress cracks and see if any moisture coming in.3rd check out the HVAC systems.

Quote from @Ursula Leake: Hi Jaryn!

You also need to perform a thorough inspection of the unit, checking for potential indicators of leaks, pests, unauthorized people or animals, and overall housekeeping. 

Do they communicate well, do their vehicles leak oil or are messy, do they enjoy talking to people, do they smell like cigarettes? 

Water and sewer pipe leaks (though small) have been discovered under many of the homes.  

If you don't fix your buildings, things like roof leaks can cause greater damage.