The next limiting factor is skilled labor. Often the demands and expectations of a well-paying client limit who you can use to perform the work. For example, tree trimmers and cell tower installers both require individuals who have great agility and fearlessness. They are never abundantly available.
Stay on course
In his book, Good To Great, author Jim Collins identified a discipline he called the Hedge Hog.
Collins was referring to the ability of highly successful companies to identify their path and stick to it no matter how many other apparent opportunities came across their radar. The same discipline applies to your business. Once you have methodically designed and implemented your business model don't lose sight of it. Test every opportunity against your business model to determine whether it fits or not. If not, let it pass. If so, make
the slight adjustments you need to in order to capitalize on the opportunity and grow your business.