Spanish to English Tech/Engineering Construction / Civil Engineering

Term comes from Supply Offer in Iberian (more or less) Spanish. The complete phrase is:

El montaje y certificación se realizara tarifa por administración.

I suspect (very probably wrongly) that it might mean at hourly rates. But there are other definitions floating around that refer to it being used to describe an "all included cost", where any extra materials, etc are bought by the supplier.
Any ideas?
Many thanks