There is a sticky on the top of the ROTC forum regarding colleges that give various discounts for ROTC students. Make sure that you contact that school to see if they are still offering that aid.
I do agree with Keyz that many states will limit OOS students. For example, I know VA limits OOS to no more than 30% .
You should also re-think this if this is the only you can afford to attend that college. The reason why is what happens if you decide once in ROTC that you don't want to be in the military? Now you are stuck either trying to find how to pay for OOS without ROTC or staying with it and owe the military 4 yrs of AD upon graduation/commissioning. Let's be honest the reason they give you that 1st yr to walk with no penalty is because they know many kids "think" that they are 1000% this is what they want, but once there they realize it is not!