http://talk.collegeconfidential.com/financial-aid-scholarships/1678964-links-to-popular-threads-on-scholarships-and-lower-cost-colleges.html links to lists of low cost colleges and merit scholarships. Depending on your actual price limit, some of the schools may be worth looking into.
No specific major is required to do pre-law. However, high GPA and LSAT score are needed. See http://lawschoolnumbers.com . Philosophy and math majors tend to do well on the LSAT, presumably because the logical thinking involved in those majors helps give practice for the LSAT’s logic puzzle section.