In order to let the cost of PCB can be as low as possible, there are many factors that must be taken into account:

1. The size of the board is most important. The smaller board, the lower the cost. Part of the PCB has become the standard size, as long as the cost according to size as it will naturally decrease.
2. SMT will be much lower than THT, because the components on the PCB will be more intensive (also small).
3. On the other hand, if the components on the board is very dense, then the routing must also be more detailed, and the equipments should be correspondingly higher required. The cost of these problems,compare to reduce the PCB size with more savings.
4. The more layers the higher the cost.
5. Drilling takes time, so NTHs the less the better.
6. Buried holes is more expensive than NTHs. Because the buried hole must be drilled at the junction.
7. Hole size.
8. Others.

Last, the equipments in manufacturing is more complicated, the cost will be more high. Understanding of PCB manufacturing process is very useful to save the cost. CMD Circuis have professional working group to analyze and control the cost of material.