Cameron,
I'm glad you started this discussion. My company has plans to just this and becoming vertically integrated in every possible facet of the revenue chain. Right now, we are focusing on building the construction subsidiary to lower costs in our BRRR strategy.
An example of what we want one of our deals to look like:
Buy a multifamily property (4 units) on a huge lot that is capable of adding more housing on it. Have our excavating/concrete company dig and pour the foundation for the additional living quarters, our carpentry company complete the framing, our partnerships with electrical, siding, and gutters companies do their part, and our own roofing company to finish the roof. Obviously, there are a lot of missing pieces in the construction process and those will be filled in by subcontractor for the time being, but our goal is to have a hand in each step in the construction process eventually.
Where I have the biggest issue is selling that idea to other potential partners. Specifically, I have trouble convincing others of the merits of being paid in equity in the business instead of being paid in labor. As part of the BRRR process, we hold the property after the additional unit has been constructed, which leaves a recurring stream of revenue, but subcontractors don't necessarily want to be in the real estate investing business. People would rather have a larger up front pay day instead of an equity stake in a cash flowing property.
So how does one convince others of the merits of a vertically integrated, large scale BRRR company as opposed to working individually on the same projects?