LARGO — Tihomir Botchev told his neighbors he was a contractor.But authorities say the 32-year-old, originally from Bulgaria, actually made his money by running a transcontinental crime ring that defrauded several financial institutions out of at least $3.1 million over the past four years.The operation involved using fake documents to get credit cards and luxury vehicles, which were then resold overseas for sometimes double the value, Pinellas Sheriff Bob Gualtieri announced Friday morning.Authorities raided Botchev's Largo home off West Bay Drive on Thursday and arrested him and four other men on racketeering and conspiracy charges. A judge set bail for each of them at $500,000.The investigation, which began in 2008, is a joint operation of the sheriff's economic crimes unit, the U.S. Secret Service and the Florida attorney general's statewide prosecution office. It is ongoing."This is one of the largest investigations we've had in the Tampa Bay area," said John Joyce, special agent in charge of the Secret Service's Tampa office. "Certainly the most organized. … The scheme itself is the most involved we've come across."Authorities are still looking for five other men they consider to be main players in the crime ring, although Gualtieri said hundreds of others may have participated in the scheme over the years.At a news conference Friday morning, Gualtieri and Joyce used giant diagrams to explain how the crime ring worked. They said the group used three main schemes:• Recruits would be given fake documents to get credit cards, which they would then max out on purchases from various shell companies in Florida and Illinois linked to Botchev. Botchev would then withdraw cash from the shell companies' accounts. Banks would never be paid. Officials estimated the ring got about $1 million this way. • Suspects used fake documents to get car loans for new BMWs, Audis, Infinitis and other luxury vehicles bought in Florida, and then they registered them in Illinois, which had looser rules when it came to proving satisfactions of liens. The crime ring would then ship the cars overseas to places such as Lithuania, resell them and never repay the bank loans.• Using cash from the credit card scheme, suspects also would use fake documents to buy used cars from local dealers and then get fake loans for those same cars from banks. Meanwhile, the ring would ship the used cars overseas, resell them and never repay the banks. Officials estimate the ring got about $2.1 million from both of the vehicle schemes.The group duped more than a dozen financial institutions, including Chase, Fifth Third Bank, Bank of America, BB&T and Grow Financial, among others, officials said.In addition to Botchev, those arrested Thursday included Ivan Petrov, 31, Georgi Angelov, 28, and Martin Jordanov, 27, all of St. Petersburg, and Lubomir Sandov, 47, of Clearwater.Authorities are still looking for these men: Ivan Staykov, Kiril G. Dinev and Ivaylo V. Georgiev (a.k.a. Rumen Naydenov), all of Chicago; and Nikolay Poibrenski and Atanas Todorov Zagorov, who are believed to be local.Detectives said someone from inside the organization tipped off authorities to what was going on. But it took authorities years to put the case together.Officials in Florida and Illinois have already made changes as a result of this investigation, Gualtieri said.He said Illinois has tightened its policy regarding showing proof of loan satisfaction, and several of the financial institutions involved are requiring physical inspections of cars before they issue a loan.All of the people involved in the scheme are from Bulgaria or other eastern European countries, officials said. Some, including Botchev, entered the United States legally, then became citizens.Botchev himself moved to this country a dozen years ago, sheriff's spokeswoman Cecilia Barreda said. He lived in both Chicago and Florida. Authorities said they believe he met the others involved in the scheme through social situations.No one answered the door Friday at Botchev's one-story, coffee-colored home on Keating Drive. Neighbors said he has a wife and children. A St. Patrick's Day-themed welcome sign was stuck in the lawn.Reach Kameel Stanley at tampabay.com or (727) 893-8643.