Tradesman awaits his fate after owning up to breach.
Paul Edward Golding, 54, pleaded guilty to breaching consumer protection from unfair trading regulations between July 20, 2009, and September 7, 2010.
He committed the offence by stating that the garage conversion on Darlington Back Lane would be completed by the end of October 2010.
He also admitted two counts of fraud from August 27 and December 20, 2009.
He made dishonest representations to a woman that he needed pounds 4,000 for further materials for the conversion, and pounds 160 to submit plans to a local authority.
He pleaded guilty as he was due to stand trial at Teesside Crown Court on Tuesday.
He previously denied five counts of recklessly engaging in a commercial practice contravening the requirements of professional diligence.
It was alleged he failed to secure floor joists, to install a damp proof course, sound insulation quilts, plasterboard and an appropriate fire-rated door, and to ensure that partially completed electrical works were made safe.
Prosecutor Richard Bennett said it wouldn't be in the public interest to try Golding on these less serious charges, which will be left to lie on the court file.
Golding, of Cumberland Street, Darlington, was bailed until sentencing which will take place on July 17.