Even the best business soirees can bring little return on the investment, so deciding how much you can afford to lose -- though not something to really celebrate -- can keep all the partying and paying in perspective. Budget a set amount and stick to it. Having a best- and worst-case scenario for spending makes it easier to enjoy the party and your guests, too, because there won't be as much running around to add "this and that" right before or during the big event.
Partnering with other small and even large businesses can be a big payoff whether the party is a success or not. If you have services to offer a catering company or local liquor store, maybe in the way of editing their Web sites or printing fliers at cost or providing free haircuts for a season, bartering can be a win-win. Some companies even offer goods and services in exchange for setting out cards or linking to their business Web sites from your event site, and the more business owners you contact, the more potential for word-of-mouth and getting your own services on the minds of others who might not know of you otherwise.