How to be a great apartment hunter?

Learning to adult here. How do I apartment hunt and make sure that everything is working properly and all that. I remember being younger and living in a shitty apartment where the heater didn't even work even though they had said it did...and when we got portable heaters, the entire place short circuited. And then the more obvious ones, some doors didn't have properly working doorknobs. Less obvious ones would be outlets that aren't working. How do I avoid getting an apartment that shitty?