The Department of Internal Affairs runs the process and at the time said it was "a good deal" and that it did not need to inform the Government about its decisions.
Harley Spence, the manager of VIP Transport in the Department of Internal Affairs, said Turners was used previously because if ensured an open and transparent sales process.
"We expect higher buyer interest and, importantly, value for the taxpayer by gaining the best return."
The limos have serviced ministers, visiting politicians and the Speaker as well as the Leader of the Opposition.
The cars were introduced in 2012. Since then they have driven visitors including many royals from Prince Charles and Camilla to Prince William, the Duchess of Cambridge and baby George as well as visiting heads of state.
The new fleet of BMW 730LDs have been phased in since December. Thirty two of the 34-strong fleet were being replaced. The DIA announced it was replacing the fleet last year after three years of service because the extended warranties had run out. Nine vehicle models from six car manufacturers were submitted for the tender and DIA said the BMWs had the lowest overall cost of ownership of the ones that were suitable for the role.