As David alluded to, cash is the life blood of any business, engineering included. I've posted a little bit about sales and marketing for engineering in replies to the thread
How/where can engineering design firms for sale be identified?
The other part of the equation is managing cash. You will also be responsible for making your own estimated tax payments, including an extra share of FICA, and other fun things.
You may want to check out
Cashflow for Freelancers. I haven't read the book, but I listened to the
author's interview about variable cash flow on The Business of Freelancing podcast. It was good.
Incidentally, the author, Diana Huff, does marketing for small, family run manufacturers at
Huff Industrial Marketing. So she not only has experience as a freelancer/consultant, but is also familiar with the kind of "hard" engineering that many of us do here and the market for it (as opposed to software engineering, web design, and the other types of freelancing that get more coverage and have more dedicated resources than engineering).
- Rob Campbell, PE
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