After viewing the long list of projects above, you might be motivated to specialize in one particular type of work. I have been tempted to specialize because it is challenging to do so many different types of work. On some jobs I find myself learning as I go and having to excessively focus on avoiding mistakes or wasting materials.
When you specialize in a particular area you gain economies of scale on your materials purchases. This improves your profit margins. At the same time you minimize the cost of tools and equipment needed. The work that you do becomes second nature and the learning curve for your helpers shortens.
Choose a specialty that has high demand and that you enjoy. Your biggest challenges and your best earnings come when tackling the most demanding jobs in your area of expertise. These are the jobs that only you, the expert, can do. Pest repairs, pressure washing, painting, landscaping, disaster preparedness, alternative energy, light carpentry, fence repairs, telephone and network wiring or home theater wiring are just a few examples.