It sounds like you want to transition into owning a business, and are willing to deal with the hassle that comes with employees. I would recommend hiring a helper that you can envision running a crew, interacting with your customers, and legally driving your trucks. They will cost you a little more per hour, but it will be worth it.
Adding a helper should give you plenty of time to sell additional accounts and start managing your business. As you add accounts, start letting him maintain some of your less important properties on his own. This will let you judge his work and give you time to continue selling.
When you get maxed out with one helper, add another part time worker for a few hours a week. They can help your full time worker on a few properties, while you continue selling and managing your business.
The next step will be starting a second crew. This step will be expensive, but you can delay the purchase of new equipment for a while. Have your full time worker (crew leader) do 4 10 hour days. This will free up your equipment for you use while you add another 1 or 2 days of work.
Eventually you have a full time 2 man crew, run by an experienced crew leader, and a part time crew that you are running. Make sure you always leave time to sell, manage your business and check the other crew's work. You can then repeat the process until you are managing 2 full time crews.
Sorry for the long post, I hope something in it is helpful.
Also, don't worry about a bonus plan at this point in your business. Each time you expand you will experience a temporary pay cut, and you can also expect regular turnover with your employees. If someone proves to be a good worker for a year, you can always consider a bonus then.