MIAMI (CBSMiami) — A crafty but flawed precious metals investment scheme may land four men behind bars.

The  South Florida Sun-Sentinel reports the men are facing federal fraud charges are expected in court this week.

Arthur John Schlecht, 53, of Boone, N.C. and formerly of Miami-Dade County, Frederick Bart Gomer, 66, of Sunrise, Ricardo Jorge Padron, 52, of Miami, and Carlos Rodriguez, 35, of Miami, were indicted for conspiracy to commit mail and wire fraud, prosecutors announced Thursday.

The group is accused of operating several brokerage firms offering investors the opportunity to buy gold, silver, platinum and palladium bullion, which would be stored for the investors in depository vaults. Instead, the foursome kept the investors’ money for themselves, according to the indictment.

They allegedly diverted millions of dollars to Schlecht, his family and third parties to pay for, among other things, maid services, personal tax obligations, salary, Social Security contributions, home and vacation home construction, landscaping, remodeling, interior furnishings, automobile purchases, restaurant dining, personal travel expenses, clothing and jewelry, according to court documents.

When the Ponzi scheme collapsed, their investment companies Global Bullion Trading Group, Capital Asset Management and Certified filed for bankruptcy, records showed.