Alrighty, this is gonna be a long post.
I'm going to give you a pretty flexible food plan I made for a friend of mine who wanted to do vegetables and such along with raw meats. For this one, we made a plan for about 75% meat/organ/bone, 15% veggie, and 10% fruit.
She also sometimes added in some whole grains such as oatmeal, barley, millet, and quinoa. But that part is optional. It can, however extend the amount of food he is getting without you having to add more meat. If you do that, I would suggest 70% meat/organ/bone, 15% veggies, 5% fruits, and 10% whole grain.
1. What types of food/vegetables/fruits to feed?
Vegetables: Usually a base of pumpkin or sweet potato is where I suggest to start. From there, it can be varied greatly depending on what is on sale/cheapest/most readily available. Good options are broccoli, bell peppers of any color, cabbage, carrots, cauliflower, green beans, dark lettuces, kale, chard, spinach, zucchini, and squash. Dark leafy greens are especially nutritious and I would try to include one of those most of the time.
Fruit: Lots of varieties, I feed a smaller portion of fruit because they do have a lot of natural sugar. Good ones are apple, apricot, banana, blueberries, raspberries, blackberries, strawberries, cantaloupe, mango, pear, pineapple, cranberries. A big thing to remember with many fruits is to be sure you remove pits/seeds. This is not an issue with something like strawberries or blackberries, but apple seeds are rather high in arsenic, and pits like those of a pear or mango can cause blockages.
Whole grain: oatmeal, millet, barley, quinoa.
Meat: It is important if you are going to have a self prepared meat component in your food that you include muscle meat, bone, and organ. These three will cover most nutrients your dog needs. I was asking if you would consider feeding at least partially raw because it is much more expensive to get deboned meat. If you instead fed something like say chicken quarters/necks/frames, what you could do is give a chicken quarter for one meal and then an organ/fruit/veggie/whole grain mix for another meal.
But if you really want to cook it, then you will either have to get very good at filleting chicken quarters so you can give the bone separate from the meat or eat the higher cost of boneless meat and add in a bone meal supplement on top of it. The meat base of my dog's raw diet is chicken quarters because they are cheap, easily available, and usually a nearly perfect ratio of bone to meat. I can get a 10 pound bag of them at Walmart or Kroger for about $6-7. When looking for store packaged meat, find meat that has less than 100 mg of sodium per serving.
Besides those, chicken hearts, gizzards, giblets, and testicles are other good things to add in and are available fairly cheap. You would also want to include chicken liver and other organs such as lungs or kidneys.
As for other meats, if everything goes fine that first month, you can start adding in new meats a little bit to a time (think a bite sized piece). Usually the next one I move on to is beef or pork. Tongue, heart, neck bones, stomach, tail (beef), spine bones, ribs, etc. are all usually pretty easy to get hold of. When you are able to give him a full serving of the new meat, then you can be fairly sure his stomach will handle it well. Then you can either do combos of multiple meats (chicken quarter, pork liver, beef kidney) or you can stick to one meat and a time - get enough chicken for a week, and then get pork for the next week, etc.
2. How much per serving for 2 times a day?
I would start at 2% of your dog's current body weight. That will give you the total weight of a day's worth of food. Then you would use the percentages I mentioned to start to figure out about how many ounces of each one to give. The following website will calculate it easily for you. They say 2% for fat dogs, but I've found that 2% raw is a pretty normal intake for most dogs. Plus, it will just be a starting point. You are free t adjust it up or down according to how his body condition looks.
3. How to include lower priced foods into the diet due to monetary restrictions?
As I was saying above, deboned meats are going to be about the most expensive. If you can do bone-in meats, I would try to do that. Look for "manager's specials" - that was how I got 8 pounds of beef neck bones at Kroger for $4. Mexican meat markets, and asian markets are also excellent places to look. If you have any wild game processors or farm animal slaughterhouses in your area, they would also be good to talk to.
Fruits and veggies will depend on your area and sales, but with a large list like I gave you, you have room to look around because you would probably only use maybe a maximum of four veggies and two fruits at a time (if you prepare a week's worth of food at a time).
4. What foods to leave out?
Basic foods that dogs shouldn't eat - onion, chocolate, avocado. That one's pretty straightforward. Some that aren't dangerous but I would leave out would be things like celery, cucumber, and watermelon. Just not a lot of nutrients in those, mostly water.
5. Average prices of foods (per pound, are organs and stuff cheaper)?
Bone in meats will be cheaper. Organs tend to be very cheap at ethnic markets. I can get pork heart at my local asian market for about 29 cents a pound, beef tongue for 75 cents a pound, pork neck bones for 70 cents a pound...the list goes on. Especially if you hit them during a sale, usually Wednesdays for mine.
A couple things I would consider supplementing would be goat milk, fish or coconut oil, two-three raw eggs per week, a probiotic, tripe (either green, or I'll use this canned - Petkind Pure Kindness
Also, because plants are not as easily digested by dogs as they are by us, they'll need to be processed in some way to be optimally digestible. I suggest breaking them down in a food processor, but you can also steam them or boil them in water (as long as the water is included in the meal since boiling leaches many nutrients into the surrounding water, otherwise there are quite a few nutrients that could be thrown out with the water used to boil)
I'm getting a bit brain-dead. If I read this over later and see anything I feel I need to add, I'll let you know. Feel free to ask me any questions about it or clarify anything.