Well, I have several places to shoot for free, My best friend has an area where I can shoot about 75 yards, One Son has an area (when crops are out where I can shoot over 100 yards safely, his close friend (and a friend of mine) has a 300+ yard range. Another Son also has an are where we can shoot 50 yards or so.
However in order to purchase from the CMP, I maintain my membership at Linden conservation club, cost me a $100 a year (CMP requires that you belong to a NRA affiliated club).
Off topic, but you know this doesn't mean you have to belong to a shooting club, right? You can join Indiana State Rifle and Pistol Association for $25/yr or cheaper if you go multiple years, or the Garand Collector's Association for $25/yr. If you want to stay at Linden, that's fine, but just know that there are much cheaper options if you're just looking for CMP eligibility.