I used to work in property management, I can tell you that your landlord hates you. Really. You are just a number and a dollar amount to them. Best thing I can recommend is that you read your lease very very carefully and follow that up with getting very knowledgable with the rental laws in your area. THe more you know, the more ammo you have as renters. For example, here in California the landlord MUST pay you back your secruity deposit within 21 days of your leaving, and if there are deductions they need to line item them and justify them. The best thing you can do is a walk-through with your landlord before you leave making sure that there is nothing that you disagree with as to the condition of the property. But really, read your lease and read up on the housing laws. It will save you time and money.
I don't understand where these terrible landlords come from. I rented an apartment in a big complex before I moved to this rental home, and even at the apartment my landlords were really chill for the most part. For example, when I signed the rental agreement I marked that I had no pets (cuz at the time I didn't) and they charge you a $200 pet deposit for each animal, plus dogs had to be <40lbs and certain breeds weren't aloud. But after a few months I got a cat, and after a year and a half had passed my girlfriend moved in with her big ass black lab/pitbull mix. The landlords (they were 2 younger women) eventually found out I had a dog and cat, and never said a word about it, even when my cat got out and I called them asking to keep an eye out for him. They were pretty cool, especially considering that I went into the office and called them both racists for not letting me have the baby pitbull I was trying to adopt from the humane society.
My landlord just always has guys constructing on the building , (because of a cafe opening infront of my house ) never gives me notice and is here all week with a drill and hammer from 8 am to 2 pm , its sorta shitty but I smoke weed inside and no one has said anything after 3 months so must be in the clear by now