Concrete garage floor

A double car garage floor has some major wear on it, salt damage, pot marks etc. 40 years old. It also has wandering cracks that have been there for years and have been quiet for years.

What's the best method of dealing with this floor?

What would they cost to repair?

1.} I've considered having it covered with a new layer of concrete on top of the old.

2.) I've also considered having leveling cement instead. (cost is a consideration here)

Cicero