Plan for food, litter, routine veterinary care, insurance or an alternative contingency arrangement, grooming supplies and reliable care when you travel. Larger equipment can also cost more to replace, particularly if a growing cat outgrows a carrier or sleeping area. Build your budget from actual local quotes and the products you intend to use rather than assuming every month will be identical. Some expenses arrive annually or unexpectedly, so a small monthly allowance for replacements can help.
Separate essential care from optional decorative purchases. A sensible starter setup can be expanded once you know the cat's habits. Review costs as the cat ages, because dietary, medical or access needs may change. The purpose of budgeting is to keep care dependable throughout the cat's life, not simply to make the initial purchase affordable. Convert annual quotes into monthly allowances: an illustrative £240 yearly expense needs £20 set aside each month. Keep emergency costs separate from predictable bills.
For product comparisons alongside this advice, see Velvet Nest and Sterling Court litter tray. The details below explain their sizes and uses.
Further reading: cats.org.uk; cats.org.uk; gov.uk; gov.uk; gov.uk.
Velvet Nest
Sterling Court litter tray
Taj-MeowHall