Search by the complete model number

Retailers may sell closely related models with different accessories or filter systems. Copy the full model code and look for the corresponding manual and replacement-parts list. A filter advertised for the same brand is not enough; confirm the compatible models and what the pack actually contains.

Check whether filters are washable, replaceable or a combination of both. Washable does not mean maintenance-free or indefinitely reusable. Follow the manual's method and drying instructions, and do not invent a replacement interval from a review about another machine. If spare filters are needed while washed ones dry, include that possibility in your comparison.

Build a modest ownership estimate

Use the current price of the correct filter and any stated maintenance schedule to form an estimate, while leaving uncertain costs clearly marked. In a hypothetical example, a £100 vacuum plus £15 of replacement parts during your chosen comparison period totals £115. A £110 alternative with £3 of required parts totals £113. Neither figure is a real product offer or a forecast of repairs.

For a bagged vacuum, establish the correct bag pack size and price. For a cordless model, check whether the battery can be replaced and what the manufacturer currently offers. Do not assume a long advertised runtime describes the highest power setting with every powered attachment fitted.

Keep performance and repair costs separate

A low parts bill does not compensate for a vacuum that is unsuitable for your floors or awkward to empty and carry. Compare the attachments you need, storage, weight and access to narrow areas. Ask whether the sale bundle includes a tool you would otherwise have to purchase separately.

Finally, check that the seller identifies the machine's condition and provides the relevant warranty information. A discontinued model can still be useful, but access to matching consumables deserves attention. Save the model code with your purchase record so that the next filter order does not begin with guessing from the colour of the vacuum.