A store owner from south London has pleaded guilty to selling a bladed tool to a council volunteer aged under 18.
Jim Turner, who featured on the cover of DIY Week on March 20, was visited by officials from Croydon Council's trading standards branch.
One of Mr Turner's employees at Portwood Supplies sold the youth a snap-off blade in November last year and Mr Turner went to court as a result last week.
Croydon Magistrates Court heard how his current premises are opposite his original trading site and he had not moved his 'challenge 21' signage across from the old store.
However, while critical of the lack of signage the court also heard it was Mr Turner's first offence in several decades of trading and took into account the fact he has now placed signs around his premises.
He was ordered to pay £1003 in court costs, £750 fine and also a £15 'victim' payment.
He told diyweek.net: "I put my hands up in the first place and I'm glad to have what's been a rather expensive exercise behind me.
"I hope that if anyone else sees this they'll think about their sales and hopefully avoid going through what I've been through."
Mr Turner also said he intends to put up the guide published in DIY Week on March 20 to help advise his staff on the dos and don'ts of age restricted sales.