I&#x27;ve been a sole proprietor in architecture&#x2F;design for over twenty years. [1]<p>1. Have separate savings and checking accounts for the business and run all the money through them. It is typically easier to set these up as a sole proprietor because the personal liability works in your favor with regard to the bank.<p>2. Use separate credit cards for purchases, but to a first approximation don&#x27;t purchase anything for which you cannot invoice a client...i.e. you don&#x27;t need a new Macbook Pro and you definitely don&#x27;t need to spend time pretending that shopping for one is work.<p>3. Generally, if you &quot;incorporate&quot; an LLC is the way to go because you don&#x27;t necessarily have to pay yourself a salary (check with an accountant) and can just disperse money to yourself much like with a sole proprietorship.<p>4. Also check worker&#x27;s compensation laws in regard to sole-proprietorships, LLC&#x27;s, and S-corps. This is a place where I&#x27;ve seen people run into trouble.<p>5. General advice, contracts matter, but client relations matter more. You probably don&#x27;t want to lawyer up to enforce some term of your contract. You&#x27;re better off stopping work when you don&#x27;t get paid quickly and that means having prompt payment terms in your contracts. It&#x27;s even better to require a retainer payable against final invoice.<p>Good luck.<p>[1]: Architects have personal liability for errors and omissions in projects under their seal <i>and</i> because that is the vast majority of my liability <i>and</i> because an LLC&#x2F;S-corp only protects against contractual liability and that is rarely an issue due to common clauses in industry standard contracts, I&#x27;ve never bothered with a corporate entity. YMMV.