OP, I think your question is: "will homecooking for my dog be less expensive than feeding her expensive commercial kibble?"
In my experience, a resounding no! Sorry.

I have home-cooked for allergic dogs from necessity, but it is really not cheaper overall. Nor is it necessarily better for the average non-allergic dog. You need to spend time making sure that the dog's dietary needs are met in home cooked food, and that requires a lot more than just chicken and rice. The factor in added vitamins and other supplements, and the time spent shopping for and cooking the food . . . it all adds up.
I usually feed the best "premium" commercial food I can find that suits my dogs. Generally, the better the quality of the food, the smaller the portions you need to feed. Most people find that cheap (non-premium) foods with a lot of corn are a false economy in the long run. You need to feed larger portions, and tummy upsets and allergic reactions are more frequent. I also supplement the premium kibble with raw veggies and eggs, fish oil, yogurt, glucosamine etc., but my pups are very pampered.
You can research the pros and cons of various commercial foods, home-cooking and raw feeding at various sources on the internet. Here is one that links to a lot of resources:
http://www.dogfoodanalysis.com/information.html
Be warned, people in the dog world can get very passionate about feeding.
My friends who raw feed (probably the most expensive option they spend $$$$!) think I am quite neglectful for feeding premium kibble.