Bearing in mind the two primary reasons for incorporation (limited liability and tax planning) your choice would depend on several business-based factors that would maximize your liability protection and optimize your tax situation.
Here are some things to keep in mind when making this decision as it can be costly on the road ahead:
1. What are the major risks inherent in your business?
Be sure to list not only risks leading to formal lawsuits, but risks that affect your ability to earn revenue and keep costs under control.
2. How often are and to what degree will risks affect your business decisions?
With respect to lawsuits, determine how likely are participants in your industry to become enagaged in a lawsuit. Looking at your processes be sure to identify those "jump off" points that could spark legal action.
3. Are there any peculiar accounting practices that are not currently transparent for tax or corporate association purposes (relationship between company and owner)?
Talk to an accountant for this one as this questions addresses complex transactions and relationships in small business.
4. What is your vision for growth?
It is best to begin operating as you envision how the future business will be in the future. If plans are to go public, then operate as a public company - observing how to accomplish goals as public companies do.
5. What is the "end-game"?
Be sure to discuss with your accountant and attorney your business succession plan. Whether the business is an overnight success, durable bread winner, or an idea "whose time has not yet come", be sure that windup and succession are clearly mapped in your plan.
6. What is your current tax situation?
Assess thorougly your current tax situation. Income from the business can come in many forms. Be prepared to account for those varied revenue streams.
7. Any outstanding litigation?
Be sure that your starting the business does not aggravate any current or outstanding lawsuits.
As an accountant, I've provided some of the basic questions asked before an incorporation is performed. If you have further questions, please do not hesitate to let me know.