Don’t forget to eat liver occasionally as it is very affordable and nutritious.
Always use butter to cook/serve vegetables for best assimilation of minerals from the greens.
Make stock at least once a week. Fish stock cost very little (your fish monger may give fish carcasses for free) and are full of nourishment and have protein-sparing effect. So, you can get by with little meat in your diet when you use properly made stock.
Use congealed fat from stocks for cooking too.
Always buy/use butter or a small amount of lard… yes!… LARD!
Margarine and shortening may cost less but it’s a false economy, one that leads to numerous diseases.