I've read posts where people discuss accurately understanding their operating costs. I'm considering starting out doing all the work myself and owning all of my equipment. This means no salary expenses (other than my own) and no equipment payments. The main costs that I can see would be gas, equipment maintenance, advertising & insurance. It seems like the expenses are fairly low and that most of what you earn is profit. Am I missing something? The reality may be very different and I'd like to hear from those who have been doing this a while. Thanks.