The $1000 bill of the ball

School students preparing for the increasingly costly ball season are facing an unexpected extra charge - a fee to try on dresses.

The Secret Wardrobe, an upmarket dress-hire shop in Auckland's Parnell, can get so overrun with excited teens it has introduced a $25 levy to deter time-wasters.

"We get girls coming in who will try on loads of dresses and then say, 'Oh, I'm actually getting one made'," said owner Carol Abernethy.

"But this year we haven't charged anyone the fee, and even if girls try on more than five dresses we tend not to enforce it."

Abernethy said anyone who paid the fee would have it knocked off the hire price if they booked a dress.

That will be good news for girls looking to keep skyrocketing ball bills to a minimum.

With the season fast approaching, dress shops are inundated with girls willing to spend thousands of dollars, while hairdressers, makeup artists, spray-tanners and limousine companies are also in hot demand.

Jessica Beswick, a 17-year-old student at Westlake Girls High School on Auckland's North Shore, has spent $395 on her designer black gown and almost $700 overall.

"I spent about one month searching for my dress this year - it's probably the most important part."

That's small change to some girls who shop at the exclusive Modes boutique in Newmarket.

Manager Diane Stephenson said most dresses sold for $250 to $900, but "lavishly beaded one-offs" cost up to $1800.

Their dresses are so popular they attract schoolgirls from all over the country.

"We had one girl who had travelled from Invercargill, specifically to come to Modes and find her ballgown," Stephenson said.

But looking great means nothing if you're banned from the ball.

And with concerns about drunken students on many parents' minds, more schools are planning to breath-test ballgoers who appear to have been drinking.

Secondary Principals' Association vice-president Paul Daley said those schools wanted to single out the few students who "destroy" the night for everyone.

"The decision to do it is probably based on whether they have experienced a number of difficulties with balls up until now, and how the students acted then," he said.

"I think more schools are doing it, but I'm not sure how quickly it has grown."

Wellington's Tawa College has been breath-testing students who appear to be drunk since 2003.

Principal Murray Lucas said only one student had been sent home.

"We started doing it after an incident at another school and it's obviously a good deterrent because we've had no problems."

New Zealand's largest school, Rangitoto College on Auckland's North Shore, has been breath-testing ballgoers for five years, with "very few" incidents.

Deputy Principal Alison Cleland said parents gave the school permission to test any students who appeared to have been drinking.

"The students know we do it and it puts them off. It's more of a preventative measure than anything."