If they don t seem to be running an efficient business, it s going to cost you money. Most agency CEOs are great salespeople and very quick on their feet. But, unfortunately, they won't be running your account. Get a commitment on how much time they will be devoting to your account. And try to find out what the agency's retention rates are.
High turnover is a bad sign and can seriously compromise service.
I was the research director at two agencies, so consider my point of view somewhat biased. But unless you have a complete and nuanced understanding of who your customers are, what motivates them, and what their relationships to the Internet are, your online marketing will be highly inefficient. And even if you think you know your customer, you might be wrong. For that reason, research is essential, and it should be one of your agency's core competencies. Decades have passed since Ogilvy published his book, and a lot has changed.