Be gentle with me... :)
DP and I are thinking about getting 1 or 2 cats (lots of rescue cats seem to come in pairs). We are trying to figure out if we can afford them, I have knocked up a quick spreadsheet using premium bits as worst case scenarios - it'd be great if someone who knows could have a look and critique?
INITIAL COST - £350ish
Adoption fees £80, Beds £20, Scratchpost tree £35, Grooming £10, Toys £10, Microchip cat flap £70, Collars £10, Food balls £10, crates £30
MONTHLY COST - £270ish - ouch! 
PAy monthly vet plan for vaccs etc £60, Insurance £42 (based on average, haven't got quotes yet), Cat litter £40, Food £60, Boarding £27
Do those figures look at all realistic - we want to be very sure we can afford these cats (going by this we cant
) - is there anything major we've missed?