Earth's rotation and mass calculation

As the earth rotates, it imparts a "centrifugal force" on objects which
would lessen their weight. And this varies depending on your elevation
as well as latitude. (at the pole, there would be no such "force").

And then there is the issue of the earth not being round, so I assume
that gravity is not even everywhere on earth.

When NASA calculates an object's mass for a space vehicle, must it take
the above stuff into consideration, or is that so tiny that it isn't
even worth considering even for unmanned probes that must travel a
precise path over 10 year period ?

(I realise that a true scale simply compares the weight of two objects,
but the problem is then shifted on how to manufacture the reference
object so its mass is absolutely exact)