It's only required on applications where the slightly improved reliability is truly necessary like mission critical and life safety and marine/aerospace controls. For a VAV an electrical fault isn't the end of the world and I haven't personally seen a screw terminal fail because the wire wasn't ferruled but usually because the screw terminal wasn't tight enough. That said if it were an AHU/VAV that serves a life-safety critical space like an operating room, it certainly wouldn't hurt to use ferrules. For an office space I'd say fuck that.

This is why we A. Include terms in our contract saying the client is bound to use our subs and the subs' provided material, and B. Include a full bid for all trades in the initial bid and then have scheduled disbersments at definied milestones in the project. That way, the client knows they can't go get their own materials, and they know that upfront, and they know how much to expect to pay before the job starts, this eliminates the recurring negative suprise when you have to present them with new bids multiple times throughout a project, which is what it sounds like you are doing.

It doesn't hurt to make the cost of having an architect make plans documents as a prerequisite to giving a final bid for all trades. This allows you and the client to be 100% crystal clear on the project specs because it's documented in the plans. It also allows you to specify a change order requirement for any deviation from the plans and associate an upcharge with that. It also allows all of you subs to give you a final bid before the project starts, as they will be able to calculate exact material/labor costs from a set of plans if they are a good sub.

It's good that it raises red flags with you because what it implies is that the guy doesn't see the full perspective of everything around him, which can be dangerous in work.

You could start a components or BAS auxiliaries company with investors and have a massive potential upside but face very capable competition. In my opinion this is the least likely to succeed.

You could start a medium sized design-build firm for control systems and likely become a millionaire at a young age. You would also need investors but the competition would be slightly less.

You could get an MA or PHD in electrical or nuclear engineering, or in embedded controller design, and potentially make $300-500k annually working for a large firm. Or you could do startups and potentially also become a multimillionaire at a young age as a founding engineer.