I've been making my own yogurt for years. For us, it is very cost-effective but I don't do it for that reason, I do it because (a) my kids love it and (b) I know what's in it. Organic milk is relatively cheap where I am and all that is in my yogurt is milk, vanilla, a little yogurt for the culture and a little bit of sugar (1/3 cup). I used to make vanilla bean yogurt by scraping vanilla beans into it but I simplified the process by just adding part of a commercial vanilla bean yogurt cup to my lukewarm mixture before curing, along with a tablespoon or so of vanilla. That gives it the active culture it needs as well. Probably introduces a little bit of 'outside' unknowns, but it is only a very small amount.
I am a homemaker so the curing time isn't a big deal to me. I just turn my oven on to get the temp to 110, turn if off and put the yogurt in (in mason jars). I turn it on again to get it back up to temp about 2 hours later and in another 2-2 1/2 hours, it's done. My kids' favorite time to eat it is right out of curing, when it's still warm. It's a little more custardy than commercial yogurt but we like that.
I have used 2% and whole milk. Both work, but the whole milk makes a creamier yogurt which is a lot more popular at my house. I sometimes have leftover whipping cream or half-and-half from other recipes and I put that in, which makes it even better
We use it every day for smoothies. We also like it plain (because ours is slightly sweetened vanilla flavor) but also with fruit, honey, and I like it with toasted almonds and dates.