A deft personalized introduction to entrepreneurship. Smith presides over The Business Center, which furnishes word-processing, bookkeeping, telephone-answering, messenger, copying, and related commercial services from chaotic quarters on Manhattan's Upper West Side. Founded on a $2,500 shoestring in 1977, when Smith (then 43) was fired from her job as an executive secretary, the venture grosses over $500,000 annually, catering to a client list that ranges from start-ups (with no office resources) to Fortune 500 companies faced with excess work loads or deadline crises. Covering the gamut of required topics (from pre-plunge preparations to cash-flow management to dealing with government), Smith admits to making every conceivable mistake. The putatively sympathetic First Woman's Bank rejected an application for a working-capital loan because her accountant had cooked the books to show small losses for tax purposes. A discharged employee who lodged a complaint with the state labor board had to receive a pre-hearing settlement: a judgment anywhere near the sum sought would have put The Business Center out of business. (In a lighter vein, Smith confides her envy of a friend who owns an extremely successful restaurant that takes neither reservations--to the benefit of its bar trade--nor credit cards; he never has to worry about cash flow, let alone collection.) Other, heterogeneous topics include: the benefits of hiring retirees and the handicapped; the stresses that can arise from ""the illusion of autonomy""; the prudent way to acquire advanced technology. Less broad, perforce, than McVicar and Craig's Minding My Own Business (1981)--but effective within its own compass.