I had six cats when my babies were born. One cat is a long furred cat. I kept taking him to the pet salon to get shaved every few months. He still does in the summer. My husband cleaned the litter box everyday, and kept the litters fresh. We switched to clay litters during this time, since it is cheaper. We installed air cleaner for the house, took most of the carpets out, and replaced with wood floor where we could. All the cat toys were replaced and renewed often. I took all their pet beds out and used old blankets to lay out in a shape of doughnuts, or plastic bucket with rags inside for them to sleep in. These 'doughnut' blankets were washed often. The covers/sheets on the couch were also washed often. I didn't have the time to wash the cats as often as I did before my babe was born, but when I did, I use very well diluted dish washing soap and rinse the cat veeery well. The dishwashing liquid soap gets the grease off the fur the best. I often wiped the cats with Listerine to keep the coat clean.
Since, we moved, and now the cats are in the basement. We still have air exchanger for the house and no carpet at all.
Also, I make their 'tree house' with with cardboard boxes, yarn, hemp rope, tree branches and whatever I can find, nailed and glued with glue gun and duct tape. It’s cheaper to make one than to buy a cat furniture from a store. It is easy to replace, and can make one to fit into the space and size that is allowed in your house/room.