1. loan can go how much
2. history of the car - 1 owner or 2 owner etc, accident free or not
3. engine type
4. FC - per tank / km
5. monthly maintenance
http://www.blogsmithmedia.com/www.autoblog.com/media/2007/04/kbb.jpg
Here are a list of cheap cars as compiled by the Kelley Blue Book. Though it certainly does not apply in this part of the world...