As somebody already said...if the school fields a JV team, run away. One thing to remember in college is that as you progress in years you aren't just competing with the incoming freshmen, but also transfers. If it is a successful program, you can see quite a few D1 transfers come down who weren't going to play on their D1 teams...but can start on the D3 team you are on.
This happened to a good friend of mine's son. He was on JV as a freshman but making good progress (got called up for a few games) and was on track to be in the mix to start in the OF his sophomore year. That team made it very far in the D3 postseason and had lots of transfers the next fall. Even though this kid had made great progress the year before, he got buried again on the JV due to the D1 talent that came in. Same thing happened his junior year and he saw the writing on the wall and left the program (and quit baseball, but stayed at the school because he really liked the school).