haha we are in the same boat. Been in our house 17 years and still working on it. We are never done. Windows is my next project.
We wanted to do windows year ago - but WOW - they are expensive. I can handle lots of stuff like the deck, putting in floors, adding a wall, etc. - but the windows was too much I thought.
Of course after watching the guys put them in - I bet I could have figured it out. Although we bought our windows from a small local outfit, so not sure if they even would just sell them without installing them.
And - if I did it myself it would have taken a LOT longer, no doubt a missing window overnight at some point when I made a mistake, etc.