Yes, of course I agree with you hence this project.
I've always been big on vertically integrating. I think too many industry professionals look at things from their POV and decide in-sourcing is a bad idea. There are many ways to look at it, and for small business it's IMHO not as easy to put in terms of "ROI" as far as pure tangible dollars are concerned. Being able to turn things around quickly, when the cost of mistakes is low, has a huge impact on your operating mindset. You don't have to take 2 weeks to pore over every detail to MAKE SURE everything is perfect (and it still won't be) because each prototype is costing you several thousand dollars + 1-2 weeks. This applies to mechanical things as well as electrical. I recall Apple themselves dropping a few million on some high-dollar CNC equipment to live right next to their design lab in California. There's a reason they did that instead of just out-sourcing. Of course, if I had their resources...
I just received a quote for an industrial control board I designed for my day job, from RushPCB. $33k for 100 boards with a 20 day turn. These are not super special RF magic boards...commonplace tech nowadays. About 400 components, mostly passives, nothing smaller than 0402, a single 1mm pitch BGA, a few through-holes, etc... I can get 100x of these PCBs made in China, with superb quality, for <$1k. The BOM cost is ~$100 per board. That comes out to $11,000 for 100 boards. If I could get these boards programmed in a couple of days, I can do the whole run for them within a week, charge 1/4 what they do, and be quite happy with a week's work. Now granted, RushPCB is probably not the cheapest but they aren't the most expensive either. Every new CM I try in the US ends up being equally expensive. Maybe I'm just bad at finding the good + affordable ones.
I'm still waiting for that "a-ha" moment where I realize how utterly stupid my plan is but I haven't gotten there yet. The math checks out, all that is left is for me to study and learn this equipment like my life depends on it.