First hi and welcome to the Hub.
The price difference varies depending on what resources you have available to you and how creative you are. If you have hunters in your family or circle of friends you can reduce costs, you can place adds on Craigs List for freezer burnt meat, find a co op, slaughter house, wholesaler or hunt the sales and buy up big on specials to help reduce costs most of the methods involved in keeping prices down means investing in a freezer - but it's worth it.
I don't give suppliments but my girl gets a pretty decent variety in her diet including whole fresh fish, lamb, pork, beef, chicken, turkey, kangaroo - she also gets offal from most of these protein sources. I do add some yoghurt most days to her morning meal. If she ever needed suppliments I would give them but at this point there has been no need, remember that those who feed kibble also use suppliments

. I would do a good bit of research on RAW feeding so if and when you decide to switch you are confident you are doing the balance correctly.
As for recipes there are a few in the RAW section here are the links
Monthly Raw Prep
Sally's Doggie Oats
you don't
have to add veg or anything to their diets though, lately I haven't been.
Hope this helps and sorry for replying so late.