I would guess the reoccuring costs are about $20,000 - 30,000 per weekend, assuming you do not wreck / damage the cars.
Roger and his brother Bobby owns the company on the side of the car WCIparts.
I would say this is a serious hobby for them. They do it because they can.
After each race, the engine gets torn down, inspect and replace bearing, valve springs, wheel bearings, brake pads.
Just for set up and practice at each track, you have a cabinet full of springs and shocks and gears to get the fastest speed you can at each track.
Then, the silly stuff like spark plugs, oil changes, rear end fluid.
You have entry fees, tires at $1200 a set of four, a crew to pay, food, hotels, fuel for the $300,000 Renagade car hauler with a double decker trailer.Figure about 6 miles per gallon. Inside the trailer, you have a rolling work shop. A few spare engines, transmissions, rear end, rims, control arms. Other than a frame and roll cage, there are enough spare parts to build a second car. IF you are traveling away from the shop, you need to have anything you would need should it fail or get damaged with you, track side.
Plus, there is a complete second "back up" car inside the trailer too.
If you wreck the car, other than sheet metal damage, you have earned a trip back to North Carolina to NASCAR to have the car re-certified.
It is fun for me when I am on the pit crew, just trying to make our car the best it can be with what we have to work with.