I've looked after a tabby, that is about 10 - history was she lived with past neighbours, but they had to move following medical accident, leaving her owner with the effects of stroke and unable to do stairs, or walk very far (left side badly affected) - for around 3 years.
Hair - she does leave a lot around the house - and on me - and I feel for her with the warm days we have had last few weeks. She has sometimes woken me when about to cough up a fur ball (not nice for her, or me, if I cannot open door fast enough!)
When she jumps up on my lap, her claws are capable of penetrating jeans (she clenches / unclenches, and boy they're sharp going in my legs, etc).
Food - She used to like the little Go-Cat biscuits but think those have damaged her teeth a bit, and I now get her Whiskas pouches (4 for a pound at Iceland) or sometimes (for a change/if Iceland closed) Somerfield's own meaty pouches. There are different foods for different ages with advice on how much to feed. Check some packets for age range you feel most likely to have...
Mine will happily eat a couple a day, but the last few weeks with hot weather she's been spending more time outside, and while catching/ killing mice she won't eat them, so I don't believe she can be classed as 'going hungry'. Think they recommend 3 pouches a day, but I supplement with extras like a tin of Asda tuna once a week (half one day, half the next, so none left out where flies might contaminate).
Probably spend between 15 and 20 quid a month on her, but am cost conscious (Poundland charge a pound for 3x Whiskas, but 6+ months ago they charged that for 4, and some packets are much more, just relying on people putting same items in every week, and not noticing price rises, perhaps).