I didn't worry about cleaning the windows until after I moved to the northwest. Our first apartment here had single-pane windows and they would get condensation on them in the cold weather. I just left them that way until we moved and I cleaned the windows.
Our current apartment has double-pane windows, but they still get condensation on them in the cooler months. This frustrates me to no end! Even though I open the bedroom window almost every day, and I keep the heat on at night, and I put a fan in the bedroom sometimes during the day, they get and stay wet most of the time. The only way to get them to stay dry is to have the window open all day, but when it's really cold I don't want to do that.
So, I wipe them. I know that seems fairly obvious, but even that doesn't keep them dry. My husband or I wipe the edges before we go to bed at night.
I also clean them (again, usually just the edges) with different substances. Sometimes I use my vinegar and essential oil spray. Sometimes I use water with essential oil, and sometimes I use some Thieves cleaner. Every once in a while, I bleach the windowsill where mold spots show up.
I feel like I have to worry entirely too much over these windows, but I don't know how to keep them dry, so I just have to wipe them often.