I get ask this questions quite a bit. While my answer may not suit everyone, it tends to be the same; buy an existing accounting practice. My logic is pretty simple; why spend money and often thousands of dollars on overhead such as staff, travel, marketing materials, etc. with no guarantee of return on your investment?
You can buy an existing accounting practice that already has a steady stream of cash and expenses. You will be able to easily forecast the future profits of the business. You have an established client base that will continue to come back and utilize your services year after year. Buying an existing accounting practice enables you to forecast your future profits. When trying to grow the business through marketing programs (which are all fundamentally the same and have been used in most major markets already by the way) it is difficult to project revenues and expenses. It is even more difficult to know when it is not working and when it is time to pull the plug!
Even if your upfront costs may be more when buying a practice, in the long run these costs will be covered and then some. The real kicker is that you can finance the acquisition and pay for the practice with cash flow from the business. Try telling the post office you will pay them when the clients call you back from your mailings or cold calls!