Barry Sycamore, 39, of Milton Keynes, Buckinghamshire, playing the role of house buyer, would apply for a mortgage and name his stepfather, Michael Learmonth, as his solicitor, Snaresbrook Crown Court in east London was told.
David Bate, for the prosecution, said the societies would then send the money to Learmonth, who was on their approved list of solicitors.
By failing to lodge the transactions on the societies' central register, Learmonth was able to repeat the fraud time and again on the same property, Mr Bate said. 'It was like milking a cow twice,' he said. 'This was a fraud that was startlingly easy to commit.'
Mr Bate said Mr Sycamore was a 'very important henchman in the scheme'.
'Sycamore would apply for a mortgage and would always use Learmonth as a solicitor. He would use false references and false accounts.' Some of the deals were made in his own name, some in the name of fictitious characters, the court was told.
Mr Sycamore denies conspiring to defraud building societies of pounds 1,140,725 in 12 separate transactions between April 1986 and September 1989.
Learmonth was jailed last year after admitting fraud involving 56 bogus mortgages with which he obtained more than pounds 5m.
Mr Bate said the full extent of Mr Sycamore's involvement was not known because he had removed documents from Learmonth's offices when 'the balloon went up'.
The hearing continues today.