Building small cars has always been a marginal exercise, but it has become increasingly uneconomical in recent years as emissions legislation has got stricter. So it’s both surprising and entirely expected that Seat’s cheapest and smallest car is its Ibiza supermini, with prices starting at £17,955 for a 79bhp, 1.2-litre engined SE-spec car that comes with 15in alloy wheels, aircon, cruise control and electric front windows.