Aircon takes a beating in Singapore's heat and humidity, so it is usually the first thing worth flagging at a service, alongside the usual oil, filters, brakes and tyres. Independent workshops generally ask you to leave the car for a few hours or the day, then call with a diagnosis and a price before any bigger job goes ahead. Two habits regulars swear by: ask for an itemised quote, and ask for the old parts back — how a workshop handles both tells you most of what you need to know. For drivers around Serangoon and the Ang Mo Kio industrial estate, Chew Goon Motor is one of the neighbourhood workshops to weigh up.