We probably had $5000, into the car before the first race,
I kept a detailed budget for inspection, then learned they really didn't care, just got assigned a class and las based on the car, team, and judges gut feeling.
$750 for the car
$2000 for safety and brakes
$1200 for things like bushings, radiator, go fast parts
$800 for tires and wheels
Sold $1000 worth of stuff off the car
We had 4 guys and luckily we were all able to fit into 2 sets of gear. Ran pump fuel and the 1st race was only 30 miles from home, so no major towing or hotels.
Probably $300 in parts at the first race
So 10000 for the first race is not out of line, keep in mind our car has no electronic controls or sensors to go bad and replace, points and carb easy to work on easy to diagnose.
We also ordered a pre made cage which worked well, but we had a 30 year commercial welder on our team.
We get 2 races out of a set of tires and 3 out of brakes, but we are in an underpowered, over braked, light car.