They might be the most unfashionable vehicles on the road, but the cost of people carriers has soared as a lack of new stock and fear of public transport continues to drive the price of used cars ever higher.

The Seat Alhambra people carrier has jumped by almost 50pc to £18,900 compared with this time last year, while the Renault Grand Scenic is up 44pc to £9,425, according to Auto Trader.

The increases helped push the average cost of a used car to £17,366 last month, 29pc higher than November last year. Prices have jumped by almost £3,500 in the past six months alone.

One in four used cars less than a year old are now more expensive than their new equivalents, Auto Trader says.

The biggest price gaps are found among electric cars such as the Smart fourfour, which retails for £16,700 but a nearly new model will set buyers back £22,490. The Mercedes-Benz EQA sports utility vehicle is selling for almost £10,000 above its £45,200 list price.

Various factors are combining to inflate used car prices as drivers keep their cars for longer due to shortage of new motors caused by a lack of computer chips.

The shortage of sellers has combined with higher demand for cars as commuters try to avoid public transport to keep pushing up prices for buyers who are unwilling to wait.