Owning a marketing agency comes with many benefits however, like other businesses, cash flow is always an owner's main worry. You may think you have a really strong client relationship and would never expect them to turn around and just not pay or keep pushing the payment day back, but not everyone is really your friend in business. It doesn’t matter how successful a business may look from the outside, the most important factor is how it looks on paper each month. Especially for agencies that may be in a growth phase and operating from tight margins.