I love to see the turn around on cars like that! I worked as a car detailer as a second job when I got out of the Army, and I did a lot of auction cars that looked like that. But one thing I learned about cars that have been neglected on the interior and exterior like that is they have usually had little to no regular maintenece done on them either.
Give it a good tune up and keep an eye on the oil and fluid levels to make sure it's not leaking/burning for the first bit, and you should be fine.
