By Conor Hunt
Throughout its history, the tribunal has unearthed and investigated many controversies.
But critics of its work regularly point to the amount of money that has been spent to look into matters that happened many years ago.
The fees paid to the tribunal’s legal team have come in for particular attention. So has it all been worth it?
In truth, we won't know the total cost for some time, but we do know how much has been spent on the tribunal so far.
The total spend from 1997 up until the start of this year has been just over €97m, just under €50m of that was paid in fees to the tribunal's legal team.
The next most-costly expense deals with the day-to day running of the tribunal. A total of €30m has been spent on lunches, stationery, newspapers, shredding, courier services, IT and much more besides.
Other court and legal costs make up €14m.
In terms of those fees paid to the tribunal's lawyers Patricia Dillion, Des O’Neill, and Patrick Quinn have been the highest earners, with each receiving over €5m each for their work.
Another 14 legal professionals have earned over €1m.
So far €97m has been spent but what will the final figure be?
In 2008, the Comptroller and Auditor General had suggested around €190m, but last year, according to a letter to the Dáil's Public Accounts Committee, Judge Alan Mahon estimated that total costs may be in the region of €250m.
The latest estimates suggest the figure could exceed €300m.
The big unknown concerns the issue around third-party costs. Who pays the legal bills for tribunal witnesses?
It had been thought such a bill could be kept low, but in 2010 the Supreme Court ruled that the inquiry could not withhold legal costs based on its own ruling that a witness failed to co-operate with the tribunal.
Judge Alan Mahon said he will rule on the rest of such costs after the final report.
As well as spending, the planning tribunal has also raised money.
Gardaí have indicated that the CAB has collected around €19m as a result of the inquiry's work. Revenue Commissioners have said they garnered €32m.
The question some may ask is has it all been worth it?
The tribunal has cross-examined many millionaires, and it has created its fair share of them as well. Many revelations have been made and the debate as to whether the end justifies the cost will no doubt continue for some time.