There are different classifications of companies in the US, from “Sole Proprietorship” (easy) to 'Partnership" to “Limited Liability” to the different corps. My friends (and parents) recommended S-Corp for the tax reasons… my company pays me via dividends + a small salary, allowing for a smaller tax amount per year. It’s more work to manage however.
Trunki is a great design entrepreneurial story, and Rob is a good designer - I’ve dug up his work in KD’s archives.
related, there are examples of independant designers going rouge successfully: Yves Behar of FuseProjest was a frog designer at first, Scot Wilson of MMNL was at Nike & IDEO I believe, Hartmut of frog design, Jacques Gagné of Gecko Design in San Jose was a frog too, founders of inCase were ex IDEO, Whipsaw, etc etc… probably all the firms really.