Brace yourself for a terrifying story. This morning, a monstrous creature crawled up behind me. It's booming roar shook the ground, smoke billowed into the air, and children cowered behind their mother. I heroically spun around to face the demon - a dull grey Mercedes-Benz.

Mercedes saloons may not scare you, but this one sounded like a fire breathing dragon. It's amazing what blown exhausts can do. Actually, this 'near death experience' raises an interesting question. When should we stop repairing old cars?

The Mercedes is only worth £1,000, so replacing the exhaust costs a large proportion of it's value. Once repaired, the 'old steed' may only survive until the MOT. Sooner or later a line must be drawn. It's often more cost effective, in terms of money and hassle, to invest early in modern machinery. When repair costs approach the vehicle's value - be prepared to cut and run.

This message is brought to you by 'Avoid Old Bangers Ltd.'