Hmmm I really don't think honey would blow the budget. A couple tablespoons in a batch should come in at around 25 cents or less...
I've done bread and yogurt both to save money and increase deliciousness. They are each pretty easy and satisfying, though they do take a bit of time and attention. I gave up on yogurt, since I don't have a great place for it to ferment anymore (I miss my old oven's pilot light!) but if you have a nice warm place to do it, yogurt can be great at home. Different than store-bought, but great.
Here's a couple recipes I like:
I know you said whole wheat sandwich, but I never found a recipe that I loved. Instead, I have made this a zillion times and it's great, Alton Brown's Oatmeal Bread:
http://www.foodnetwork.com/recipes/alton-brown/leftover-oatmeal-bread-recipe.htmlI don't make apple sauce, but this is a great recipe for slow cooker apple butter, which is very nearly the same thing:
http://www.mybakingaddiction.com/crock-pot-slow-cooker-apple-butter-recipe/ I just leave the peels on, you can't tell in the final product and the peel is healthy.
Yogurt... here's how I do it. Bring milk (I use skim or 1%, 1/2 gal) just barely to a boil, turn off immediately and strain into a metal bowl. Whisk in 1/3 to 1/2 cup nonfat dried milk (optional, adds protein and helps thicken a little). Let it cool to lukewarm, then whisk in the starter. Whole Foods sells one in powder form that I've had great results with. I've never had good results trying to start from a commercial yogurt. Pour into containers (I always preportioned the milk into 1/2 cup dishes or tupperwares for ease of use), cover, and set in a warm place for 6-12 hours. Refrigerate and enjoy. You can use 1/2 cup of your homemade yogurt as the starter next time. Mine usually lasted 4-6 cycles before it started acting tired and I would start over with a new packet of starter.
Bread is really fun, but mileage does vary and things like flour and yeast and water are different in different parts of the country. I do get better results when I use bread flour over AP, so when I'm going for a whole wheat loaf I do 50/50 bread flour to whole wheat flour. I tried to do a wild starter once and it didn't work out. I have had great luck pinching off a bit of another loaf, growing it slowly over time in the fridge by adding water and flour every other day or so, and then using that as the basis for my next loaf. You get the delicious slow fermentation effect and it's an extremely low-commitment (read: lazy) way to do homemade bread if you bake regularly. Start with a piece the size of a golf ball and keep adding to it. Stay on the wet side of what final dough feels like while you're growing it, keep it well covered up in tupperware or a bowl with saran wrap, and it's great. Just turn it into dough and add salt in your final stage with a regular rise.
People swear by Peter Reinhart's bread recipes. Here's one you might try:
http://centerstagewellness.com/peter-reinharts-whole-wheat-sandwich-bread/Good luck!