Jenkins said he was not on vacation, however, but was adding a personal touch to his hot rod business by driving a car hauler across the country to pick up and return customers' cars. 

  
The road trips have become the norm for Jenkins, who said that 60-70 percent of his customers are from out of state. He added that he has a typical inventory of 70 cars, with about 40 being worked on at a time.

"What distinguishes us from the industry is that we are the largest-volume shop in the country that does everything in one building," he said. "There are shops that do more expensive work than we do, but nobody produces more cars than we do. We produce more every year than anybody."

He said he also separates himself from the competition by giving all customers a fixed cost up front along with a completion date. 

 
"We start with a fixed, cost which is very weird; nobody will give you a fixed price up front, but I do," Jenkins said. "I price every item on the car from the axle seals to the brake shoes; I don't just guess what it costs to restore the car." 

Jenkins said he takes in all types of restoration jobs, but his favorite runs about $20,000 and includes rust repair, a full paint job, new wheels and tires, and a new exhaust. It takes about five weeks to complete, and he said the finished product always makes the customer happy. 

 
For service parts such as brakes, ball joints, clutches, and water pumps, Jenkins said he goes locally to Gravois-Bates Carquest and Reliance Automotive. Radiators and fuel tanks are ordered from Gravois Auto Radiator, and tires come from Tire Rack, an online tire distributor, he said.

Jenkins said Automotive Technology Inc. (ATI), his paint supplier, has been a key asset to his business. The Spies-Hecker paint it supplies has changed how he does custom work, he said.

 
"Shrinkage was always just a fact of doing business," Jenkins said. "Then one day I was color sanding and buffing a car for the third time when an ATI salesman asked me what I was doing. I told him I was knocking out the shrinkage, and he said, 'Well, my paint doesn't do that.'"

The salesman stayed with Jenkins for a couple of weeks and worked with him, he said, until he verified that, in fact, the paint did not shrink.

"The standard paint makes wouldn't keep up with a quality that I needed for a production facility," Jenkins said. "In the can, Spies-Hecker is a lot more expensive than the common brands, but when it rolls out the door for us, it is a lot cheaper because it just doesn't have the problems."

He added that the paint is almost impervious to brake fluid and is completely resistant to lacquer thinner.

Jenkins said he also has a mobile marketing business that customizes vehicles with advertising messages and graphics. Corporate clients include Nintendo, Old Navy, Red Bull, and LG Electronics, he said.

 A party bus created for Old Navy's Canine Casting Call was made by customizing a city bus, Jenkins said. The job included cutting out one side of the bus and making it raise hydraulically so that the side would turn into a billboard above the bus, he said, adding that the finished product also included a built in green-screen for photography. 

 
The mobile marketing work is done in a separate 32,000-square-foot building and this year accounted for about 25 percent of his revenue, Jenkins said.

The other 75 percent of revenue comes from the restoration business, which is done in a 25,000-square-foot building. Jenkins said he has a total of 24 employees between the two shops.

At work, Jenkins said his goal is to have as much fun as possible restoring the old cars and the least amount of problems on the administrative side.

"By nature, old cars are incredible administrative headaches, so I have done everything I can to alleviate that," he said. "The formal processes here are mind-numbing." 

Jenkins said that from day one, a fixed price is set along with a payment schedule so customers know up front how much and how often they need to make payments. Progress photographs of the vehicle are sent to the customer every Thursday, and every customer interaction is logged in the computer.

"Everything is recorded," he said. "Nobody gives me verbal direction, and I don't give people verbal promises."

Prior to owning Doug Jenkins Custom Hot Rods, Jenkins said he worked on a commercial fishing boat in Alaska, worked in the oil fields, spent seven years as a general contractor, and raced World of Outlaws sprint cars.

When Jenkins moved to St. Louis in 1998, he said he started working on old cars in his spare time to help keep the family fed while he was racing with the World of Outlaws.

"It worked out that I could get a paycheck easier from working on old cars rather than racing," he said. "So I just settled into that; it wasn't a big, evil plan. I know some people start businesses because they have a job that they are good at and they want to go do it for themselves, but that was never me. I just needed to do the thing that I could for the most money, and it turned out to be working on cars."

Jenkins said he plans to continue expanding by opening shops in California and New York, where a large amount of his work comes from. "St. Louis amounts to 30-40 percent of our work, and it is the 52nd-largest city in America," he said. "That means there are 51 other cities that can support a shop like this."