Corded vs cordless vacuum: include the battery in the cost
A cordless vacuum is convenient, but its battery is a consumable that belongs in the cost.
Worked example
A cordless model costs $600, and the battery needs replacing every 3 years at $120. Over 7 years that is two replacements: $600 + 2 x $120 = $840, or $120 a year. A corded model costs $250 with $10 a year of bags and filters: ($250 + 7 x $10) / 7 = about $45.71 a year.
The difference is about $74 a year. That is the price of not dragging a cord, and only you can say whether it is worth it.
What to check
- Whether the battery is removable and replacement batteries are sold
- Run time against the size of your home
- Dust bin size and how easy it is to empty
- Noise and weight
Related
For robot vacuums, the same method applies: add consumables such as filters, brushes and bags to the yearly cost.