I have been in the same rental home for numerous years.
In the years that I have lived here, I have only ever had one issue with the heating & cooling system.
Because there is only window units & space heaters, there is not much that can go wrong. The weather in the region where I live is mild, & gets moderate in the summer. The home I live in is well shaded & there’s a lot of trees over the house. The daylight never makes the home too overheated & I am gleeful that I live in a home that doesn’t get baked in the daylight all day. When I noticed that something was wrong with the AC, I acted fast. I know I didn’t want to be without A/C for more than a few afternoons, & I was looking forward to a current A/C unit. The ones that were in the home before the replacement were 10 years old. The A/C units were rusted & had slowly stopped blowing cold air. It wasn’t that much of a problem until a current family moved in next door & took down one of the trees that was providing much of the shade that was keeping the home cool. I didn’t notice how much daylight they were blocking until they were gone. The A/C units were replaced in about an hour & my great friend and I were able to sleep comfortably that night regardless of the lack of shade in the backyard.