Over its lifespan, a car will inevitably suffer wear-and-tear. It’s a complex piece of machinery, and one that’s expected to cope with a whole range of stresses: from the weather, to sudden braking, to collisions.

There will inevitably come a point in a car’s life where the cost of repairs and replacement components begins to outweigh the cost of replacing the entire vehicle. But telling exactly when this point has come can be tricky. If you’ve found yourself on the receiving end of a costly repair bill, it might be worth sitting down to work things out. It might be that a new Vauxhall Corsa is more than justified.

What’s the cost of the repair?

Before you know exactly how much it’s going to cost to carry out the work, it’s worth getting a few quotes. Go to reputable mechanics whose work you trust. Don’t be tempted to cut corners and go for someone cheap – but at the same time, don’t go to the dealership, as they’ll inevitably charge you a premium.

A benefit of developing a good rapport with your mechanic is that you’ll benefit from their opinion on how likely further bills are likely to be.

Work out the costs and benefits

If you’ve been landed a £5,000 bill to fix a car whose market value is £3,000, then the decision to replace is an easy one. If your case is more marginal, then it’s worth getting everything down on paper. Don’t just factor in the cost of the current repair-job. Think also about things like running costs, taxation, and depreciation.

What about things that can’t be quantified?

There are a few factors here that can’t be so easily put into numbers and entered into a spreadsheet. If you have a sentimental attachment to your car, then you might be prepared to pay over the odds. On the other hand, you might find that you’d prefer to drive something more reliable – and that you need a little bit of retail therapy, in the form of a new car smell. The stress that a perpetually broken-down car can cause can often justify the cost of a replacement.

It’s easy to go with your gut. But just be aware of how much value you’re attaching to the decision. If you find that your decision is vastly more expensive than the alternative, then you might suddenly have a change of heart.