To answer your question about the two most lucrative locations I would agree with Adam and say the CSUS area. I would also say the North Turlock area in general with so many schools K-12. I have seen a lot of investors scoop up foreclosures in this area and turn them into rentals.
I get a lot of inquiries from investors concerning the CSUS area as a place for investment opportunities to possibly rent out. I have personally seen a lot of activity in the north-west side of Turlock and the areas surrounding the college, however, depending on your real estate needs and capabilities, almost any area can be an investment area. Good luck!