well, if you see my team name.... Cheap Bastid Racing.... that gives you an idea on how we operate
i do 3-4 races per weekend... costs me 50 bucks a pop per 8 lap sprint race, 75 for a 20 minute GT. 25 bucks to get in the door & camp for the weekend... Gas, food etc.... typically it all ends up being around 300 bucks per weekend for me on my lightweight.
BUT... race a 600 & you'll be going through tires at a much faster rate.... so there's another 3-400 dollars a set for DOT Race tires. Some guys can squeeze 2-3 race weekends out of a set, others are much faster & burn through a set in a weekend.
Crash & there's even more money out of your wallet. Bodywork, parts, chasis straightening, leather repairs, medical bills etc.
Basically, bring cash... lots of it... and then a credit card or two for when you run out of cash
The "Thousand Dollar Weekend" is far from unheard of.