A cafe owner charges customers more than TWICE as much - if they don't order politely. Chaii Stop, in Preston, Lancs., has introduced a new rule to help customers remember their manners - charging them more for their drink. Usman Hussain, 29, opened the Preston-based shop selling chai, doughnuts, street food and desserts in March this year. He recently introduced a sign explaining that customers will pay different prices for the same drink depending how politely they order. The sign explains that saying "Desi Chai" will cost you £5 while "Desi Chai please" will cost you £3. But "Hello, Desi Chai please" will cost you just £1.90. Usman said while the shop have never particularly experienced bad-mannered customers, he hopes the rule will encourage people to open up and reinforce the cafe's culture of "good vibes only." Soon-to-be dad-of-two Usman said: "I think it's a nice reminder to use your manners, because unfortunately sometimes we do need reminding. "We've never struggled with rude customers but since having the sign people are definitely coming in more open and having a laugh with us. "To me, the most important thing in my business is to walk through the door and be treated like you're a welcome guest in our home. "It's nice to have that respect reciprocated." Usman got the inspiration years back from a post he saw on Facebook of an American cafe who had implemented the same rule. He had kept the picture in his camera gallery for two years before stumbling across it recently - and he decided to trial it in Chaii Stop. He said: "I decided to bring the idea into our shop because it fit perfectly into our concept." As soon as he put up the sign, the staff at the shop found people coming in and being much more friendly. People even have a laugh about the sign - but it works, as it still reminds them to use their manners. Usman confessed they have yet to actually charge someone £5 for their drink - because it's rarely necessary. He said: "If a customer doesn't use their manners I point to the sign, and they immediately ask again more politely. "A lot of people can be quite rude in the mornings while they're waking up but when they see the sign it makes them think. "At the end of the day you never know what someone is going through to make them act rude, but it helps them to drop their guard. "It gets them talking - like an icebreaker - and that's what we're all about. "Any negativity gets left at the door."