As for food, I've fed a natural diet for all my adult life to my animals. Buying kibble is as foreign a concept to me as having my oil changed at a quick lube.
Even ~20 years ago I did some calculations of it being comparable in cost to higher end pet food, but I appreciated knowing exactly what was in my meals, plus no filler.
Today, seeing what a bag of kibble goes for, I imagine it's actually less expensive but haven't done any recent calculations to back that up.
We use chicken or ground turkey, no-added-sugar applesauce, canned green beans or we cook carrots (canned carrots are inexplicably expensive), a little canned pumpkin (now is a great season to stock up!), jasmine rice, sweet potatoes and a couple supplements like Missing Link and Doggie Dailies.
You quickly learn the best places to buy what you need at the lowest price. Not surprisingly, WM tends to win for large packs of chicken, no-salt-added canned green beans and no-sugar-added applesauce.
There's always a crock pot going for chicken or carrots or a rice cooker or a cooker for sweet potatoes. It is true I don't factor in the cost of electricity for this, but honestly most slow cooker things don't pull much. And I don't include the cost of replacing these appliances as they die.
My dogs are always quite healthy with good coats, good eyes, minimal joint problems and tons of energy. And never overweight. It may not be the ONLY way, but I know from results it works for my pack and has for decades.