If you haven't done at least 7 track days, NCRC requires you to run in Solo - which means you can't sign up for the 86 Cup for their events (which require Open or Point-by). The Speed SF and Speed Ventures events are OK.
In addition to entry fees and tire wear, you might also need an oil cooler, brake pads, and brake fluid. Also don't forget a helmet and gloves. And a sense of adventure!