The most challenging and tricky part of framing is building the bulkheads. All of the home communications such as water, sewers, power cables, telephone lines, ducts, central vac pipes etc. are located under the basement celling, this is why to cover all that stuff the patience is the most desirable character trait. It is time consuming job. Most of the time it is not strait forward project. Pretty often it takes time to make a special design to solve the problem.