How do I decide how much to spend on something?

"Buy cheap, buy twice" is true often enough to be repeated and false often enough to be expensive. It depends entirely on how hard you will use the thing, and manufacturers are explicit about this in their own product lines — the tiers correspond to expected duty, not to a simple quality ranking. Placing yourself honestly on that scale settles the budget question faster than any amount of price comparison.

Step by step

1. Decide the required life first.Three years or fifteen? Once a year or every day? The answer changes the sensible tier more than anything else, and it is a question about you rather than about the product.
2. Work out the duty level honestly.Occasional and light, regular household, or heavy and continuous. Most households overestimate this and buy for the imagined heavy use rather than the actual weekly one.
3. Set the limit before you see prices.A figure you can defend from the use case. Once you have seen the range, your limit will drift towards the middle of whatever range you were shown, which is a well-understood effect and is why the range is presented that way.
4. Work out what the extra money is buying at each step.Between tiers, ask what specifically changes: bearings, motor, materials, seals, serviceability, warranty length. If the answer is styling and features, the step is not buying durability.
5. Convert the difference to cost per year or per use.A machine costing half as much again but lasting twice as long is cheaper. Divide by expected life and compare, and include running costs while you are there.
6. Check serviceability at the tier you are choosing.The point at which products become worth repairing is often a tier decision — spares availability, replaceable wear parts, published service manuals. This is frequently the real difference between the middle and top tiers.
7. Decide, and do not let the top tier redefine the limit.Anchoring is what showrooms do: the flagship exists partly to make the model above your limit look reasonable. Keep the number you set.

Tips

• Where paying more reliably pays back: anything with a motor used daily, anything load-bearing, anything you cannot easily replace once installed, and anything where a failure causes damage.
• Where it usually does not: things that are superseded quickly, things used once or twice a year, and things where the premium buys appearance.
• For occasional heavy use, a middle-tier purchase plus hiring for the rare hard job is normally cheaper than buying at the top tier.

Common mistakes

• Setting the budget after browsing — The range you are shown sets your sense of normal, and the limit ends up describing the middle of the retailer's range rather than your requirement.
• Buying professional-grade for domestic use — Trade products are often specified for continuous duty, and can be heavier, louder and less convenient at home. Durability is real but you may be paying for a duty cycle you will never approach.

Questions people ask