Sorry I missed this question Marc.
At one time I sold jigs in bulk to several baits/tackle shops. I also had a website and sold jigs, plastics, and custom rods but got out of that mess when state and federal taxes and paypal fees ate up the bulk any profit. The real bonus or upside to making your own plastics and jigs is you control just about every aspect that big suppliers of the same cannot offer: in jigs it's hook size/quality in standard head sizes along with paint colors and schemes. In the plastics its having bait profiles, styles and a whole multitude of color schemes that are not commercially available.
I have one local shop that has stocked some Big Bite Paddletails 1-1/2", Pink/silver glitter tail for years. All of a sudden that color is no longer available in that size, so I cooked up some 1.5" Thump-Its in that color scheme for him and those sold better than what Big Bite offered.... better action in the tail everyone said. Another example of a bait you can make and it being just plain better than , say, a Keitect factory bait of a similar size is the Quakin Shad. I make the Quakin Shad with a twin injector using a clear plastic with heavy and equal parts of light Purple and Canada Blue, .015 glitter for the back color and clear plastic loaded with .40, and string, Silver glitter as the belly color. From late May until the end of July here that one color pattern is just flat out, "it". I fish this on a weighted [1/8] hook from a Do-It mold cast on a 4/0 extended shank wide gap. I sample out maybe a hundred of that combo in a couple months but sell zero of them. That bait cannot be bought commercially. It has to be made. I'm more than happy to tell people wanting the baits or the hook of both to look at Do-It's website store for the components to make them if they want them and I am more than happy to leave them with a paper catalog or th recipe to make the colors.
If you are considering making baits to sell in a shop, don't do it for nothing. If you're using cnc or Essential molds from Do-It or other mold vendors, remember, they are unique and not like factory baits. You control the plastic's characteristics and colors. Your time is worth money as is your need to recover what $$$ you put into the making of the baits.
