Station construction requires:
Locations for new stations are regulated to assure that stations are not built so close to each other so as to collide or choke off shipping.
To have a station built:
The Construction Vessel needs certain resources to begin construction. You can provide these resources yourself, have the architect arrange for delivery of these resources, or some combination of the two.
Note, if opting to have the architect arrange for the purchase of resources, that the availability of these resources depends on their availability in the economy in the area where you are trying to have your station built! Your architect cannot buy Fusion Reactors if there are none to be found in that area.
It is also useful to remember that the station types that a Construction Vessel can build differ, and are limited to the blueprints that are in that particular vessel's database. These blueprints are hard-coded upon construction, so the particular collection of blueprints a CV has largely depends on where the Construction Vessel was built.