Martin Gumbrell, 53, of Bournemouth, said his experience working for large companies gave him the confidence to carry out building work.
The builder has pleaded not guilty to three charges of deception and one of obtaining a money transfer by deception following complaints by three customers.
In the Bournemouth Crown Court he has been accused of scamming ВЈ800,000 from customers by lying about his qualifications.
Customers claim his work was faulty and in one case it is alleged a home he worked on in Poole, Dorset, had defects that would have cost ВЈ450,000 to fix.
This week Gumbrell admitted to the court he had failed an Institute of Carpenters practical exam because he вЂњwasnвЂ™t feeling well that dayвЂќ.ADVERTISEMENT
He said he didnвЂ™t redo the exam because he had just bought his first property and wanted to move on and earn some money.
He claimed he had worked on projects including airport buildings and runways in Saudi Arabia and as a site supervisor in Iraq, reported the Daily Echo.
He also claimed he had never told customers he had a university degree.
The trial continues.
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