Last March, when Mary Naylor started having large customers stretch payments or in some cases dodge payments altogether, she drew a hard line. "I won't touch a company today," says Naylor, CEO of virtual concierge service VIPdesk Inc., "unless there's at least a letter of intent and some cash on the table." Naylor drafts a short, legalese-free letter that the respective parties can approve quickly, and she insists on prorated payment to help cover any work done before the final contract is executed. "You need to have a candid, honest conversation from the start," says Naylor. So far most customers have respected Naylor's business discipline. "It shows you have your house in order," she says. Since Naylor instituted the practice, no client has defaulted on a debt to VIPdesk.