It was billed as the chance to become the new Donald Trump, the opportunity to follow in the mogul’s footsteps and make a fortune in property.

According to one estimate, 7,000 students thought this was a good idea and signed up for a course at “Trump University” where, they hoped to learn the investment secrets of “the most celebrated entrepreneur on earth”.

Now, however, the university is no more - and in a class legal action, a number of students are alleging the whole thing was a fraud and a demanding their money back and damages in three separate court cases.

With Mr Trump having pitched his presidential bid on his stellar business record, the litigation over Trump University may not only cost him financially but is certain to be seized on by opponents in the months ahead.

The message from Mr Trump’s opponents is a simple one. If this is how he operated one of his businesses, can he be trusted to run the country?

It is already a theme which has featured in attack ads, such as one produced by American Future Fund, a conservative group in which disgruntled former students spoke of their experience.

“I am a single mum. Based on the fact it was Donald Trump, I signed up. I made a huge mistake trusting him,” said Sherri Simpson. “America, do not make the same mistake that I did with Donald Trump. I got hurt badly and I would hate to see this country get hurt by Donald Trump.”