Three items account for 80% -
1. Tires = 8 sets = about $9K
2. Entries = about $7K
3. Brake pads = about $2K
4. Tow gas = about $1K (we happen to live seven miles from Blackhawk, which is about 6 races per year for us)
5. Fuel for the crew (family) = about $1K
That's about 20K of the 22K. The rest is wear parts like axle CV bearings and stuff. A couple gear sets to dial in tracks or replace pitting sets (Hewland Classic in England is by far the cheapest even with shipping, especially if your buddy needs something as well). 1 quart of brake fluid per year ($70). Oil and race gas is not to bad since we just use 10 - 12 gallons of 91 street gas per weekend ($650 - Wisconsin is a lot cheaper than Illinois due to fuel taxes).