Also a conscious decision: A nice marketplace needs a definition of the goods are, otherwise it's better to come up with a listing type business (here are some contractors, here are some job, match and do whatever you want).

By trying the editor route (which came out of the "i want spreadsheets/ no, i want text documents/ no i want slides" customer development) we hope that people over time will grasp the value of "tangible / trade-able" goods. Even if this means excluding a good chunk of business that can't be standardized.