I took contact paper and cut it to the size of the window panels and then stuck some of my paper stencils to the contact paper.
It fixed the outside but the inside still looked crappy so I just painted the windows blue.
A big improvement I think. I also cleaned the balcony and set up some plants and lights. I think the last time that was cleaned was at least 10 years ago. So some small but noticeable steps toward making the place awesome. You can come see in October for the POST open studio tours if you like.