Former FF councillor Sean Gilbride took a career break from his teaching job to canvass for the Quarryvale development and also for a seat in the Dail, the Mahon Tribunal heard.
Developer Owen O'Callaghan paid him IR£15,500 for his efforts but the bill was never invoiced to Mr O'Callaghan's company, Riga.
Yesterday Clare Cowhig, the auditor who prepared the accounts for Riga, told the tribunal that she had not looked for an invoice from Mr Gilbride.
She had been told by Mr O'Callaghan's business partner, John Deane, what this IR£15,500 was for and accepted it without an invoice as the amount was small in the overall context.
But tribunal counsel Patricia Dillon put it to her that if she was prepared to accept the word of a director in the absence of an invoice for the payment to Mr Gilbride, then it was conceivable this could be done in relation to other items in the accounts.
Ms Cowhig said there were a number of small payments made without an invoice. She said she was never told that a IR£10,000 payment in 1991 was in fact a political donation to former FF councillor Colm McGrath.
She said that when she was given the accounts for Riga Ltd, the development company of Owen O'Callaghan, there were two payments of IR£10,000 each in 1991 which were treated as expenses against the Quarryvale development.
She learned later that one of these payments went to Mr McGrath, but was still unaware of the destination of the other IR£10,000.
Ms Cowhig audited the accounts of Riga on an annual basis. There were three payments of IR£80,000 to Sheafran Ltd, a Frank Dunlop company, between May and June 1991.
But Ms Dillon said that invoices submitted by Mr Dunlop named the company as Shefran Ltd, which Ms Cowhig could not have seen when she audited the accounts.
Mr O'Callaghan is one of the pivotal witnesses in the investigation into the rezoning of Quarryvale and is due to give evidence next week.