For your cat's health, and also considering cost-effectiveness, you can choose the following foods:
1. Chicken breast is a good source of protein for cats, it is relatively affordable, and it is easy to digest and absorb.
2: Egg yolks are rich in lecithin and Omega fatty acids, which help cats have shiny fur and healthy skin.
3. Corn is rich in vitamins and trace elements, and its price is not high.

4. Carrots are rich in vitamin A and fiber, which help with a cat's vision and digestion.
5. Choosing a cost-effective and nutritionally balanced cat food can meet your cat's basic nutritional needs.
Note that regardless of the type of food fed, it should be in appropriate amounts, and the cat's reaction should be observed to ensure the cat's health and safety.