It does come down to the question....a $700 car that runs and drives, ya don't ask too many questions. Mechanical condition is really the main thing more than the others. DIY for the entire carpet would probably be around $150-$200 if done right. A replacement window motor can probably be had from another Insight owner for fairly inexpensive. If the 12V battery is bad you could throw the one in from one of your other cars.
With mudder's mod but no arduino (presumed) the car isn't getting lean burn most likely, which could be why it's getting only 48-51 mpg, unless it has the wrong tires or other issues. Obviously it needs a bit of work, cosmetically at least, but it's a $700 car, and your Accord drives now so it could potentially be a fun project to work on. I'd be down to help if I wasn't on the other side of the country!
Keep us updated!
