The most unexpected hurdle on this project was finding a building location. It took over a year to locate a place that met my requirements. The solution was a qualified and backbreaking success. The location I found (in fact, the only one I found) was an unused pole barn with a dirt floor in the back of a defunct lumberyard with an owner who was looking to eek some money out of his property. It took a year of my time to get the place closed in, insulated, a concrete floor poured, heat, electricity, lighting, plumbing and ventilation installed, and my tools up and running. It was "The Project Before the Project," but the work up front has given me the professional work space needed to build a professional quality boat.
A project on this scale is essentially a constantly evolving matrix of time and money. My up-front costs, in time to locate and build a boat shop, and the price of the monthly rent, were significantly greater than I had budgeted, but they have paid dividends in efficient workflow over the life of the project.