Disclaimer before reading my : my cats are overly spoiled and I am a bit mother hen about them and paranoid.
A few accesories are necessary, like hairball paste, that thay should take regularly. 150 nts to 300 nts depending on brand -and which brand your cat may prefer is anybody’s guess. Toothbrush and toothpaste, and schedule teeth cleaning according to vet’s instructions.
Nails could be trimmed carefully, but it is a delicate process. Hence, a good scratch post, in vertical and horizontal varieties, hopefully different textures, like a sisal rope bar on one side and a cardboard box, for instance. Cost: depends, mostly DIY -Costco boxes are great for this- or bought from 200 nts to several thousand for a cat tree.
Get a couple of balls to chase. Furry toys are better avoided, be careful with parts they can swallow. Toys should be kept in a locked drawer, to keep their attention and to supervise play. A laser pointer makes an excellent toy. Cats prefer interactive play to bond wity you, and play must have a “goal”. They have to be able to “catch” their prey or they’ll become frustrated. Here is when treats come handy. Dried fish special for cats: 400 nts.
Follow the cat’s schedule: eat, pee/poop, clean itself, sleep, wake up, play/explore. Repeat cycle. Observe cat’s rhythm and act accordingly. Best time then, to brush cat -with special brush according to its fur texture- is before he goes to sleep.
Best water/food dishes are glass or ceramic. Plastic dishes “meseta” style -high in the middle, with low borders- are also better for cats. A drop or two of apple cider vinegar in their water promotes good renal health. Ice cubes promote drinking in summer. IKEA glass dishes: 100 nts on sale.
Cats do not need weekly baths, as a matter of fact, too much bathing is bad as it removes the natural oils, causing them to have skin problems and become stinky. Cats are fastidiously clean by nature.
As to sleeping and lounging, cats may like to sleep with you but they also need their own space. Mine have “cat tepees” which are warm in winter. Gives them a feeling of safety.
Finally, you may also want to get them Frontline, Revolution, Advantix or any other montly medicine to prevent infestations. Even indoor cats may get them, really. These can be a bit expensive but they are worth it -800 to 1200 nts per pack of 3 or 4 ampules.
Remember to cat proof your house, as said before, they are curious and may escape suddenly, but also chemicals and cords and locked doors and hatches and fans and heavy stuff that may topple over. Like a baby.