Na bitte, da sagst du es ja schon selbst:

Es geht um mehrere Arten von Kosten - also wohl eher im Plural ...

Im Singular gibt es das auch gar nicht. ;-)

Scherz beiseite - ich würde hier auch im Englischen zu "costs" tendieren.

In particular, it argued that the Ukrainian fertiliser market was characterised by the existence of tolling agreements, barter chain arrangements and State interference in energy, electricity and transportation cost, and that all these factors were incompatible with a market economy situation.

In the case of remedying of a defect, we shall be obliged to bear the transportation cost, labour cost and cost of materials.

The prices are understood carriage paid to the place of consignation including package and transportation cost, unless otherwise agreed upon in writing.