The project facilitators and community leaders will need to contract a head mason to build the school. The head mason should have many years of experience with post and beam construction using concrete and rebar, and the community should trust him and his skills. When building a bottle school there is a need to think a little “outside the box” of traditional construction, so your mason needs to be open to the new construction method, and ideally be a creative thinker.
It may be best to negotiate expectations and the price of the skilled labor with one mason and allow him to then decide how many other masons he needs to contract in order to complete the build in a timely and safe fashion. Or, depending on your circumstances, you may get better value by negotiating contracts individually.