You are the owner-manager of a chain of coffee shops in Singapore, brewing and selling the latest types of expresso drink inhouse but buying all necessary factors from the market. Your 50 or so shops located around the city can seat around 20 patrons each and currently only sell caffeinated drinks. At this stage of growing your business you are considering vertical and horizontal integration. Using the theory of the optimal boundary of the firm, discuss the make-or-buy decision as well as the scope for horizontal integration and diversification of your business. What stages of the vertical chain should you consider conducting inhouse? What other horizontal markets may you integrate into?