Well you only have to spend money on safety equipment about every 5 years depending on if it's FIA rated not. FIA rated stuff is certified longer. It is a pretty significant initial investment but I would recommend having all the necessary equipment for DE's as well. Safety equipment is definitely not where you want to buy the cheep stuff. I'm not gonna say exactly how much we spend a year on racing but with one car we spend easily over 10k. With two cars the price doesn't go up that much but obviously there is more money involved with towing the car and also tires, and general maintanence items. Ask anybody that went to nationals and they will probably tell you they spent anywhere from $3500 to $7500 for the 4 day event. It is expensive but if you get into a series like SPEC E30 it's not so bad. Racing in 944 cup is an entirely different story. They won't do standing starts because god knows how much it would cost to replace one of their cute little transaxles.