What does the base station (VMB4000) do?

[funkiestj]

I already have google wifi (3 wifi access points) with 1G ethernet links between the access points (google wifi will do wireless mesh or ethernet backhaul).  Presumably I do not need the base station for wireless range.

Assuming I correct about the base not being needed for wifi range.  A base provides me with:

1. optional local storage backup (USB drive)
   
   
2. smart siren (alarm)

this similar question only kinda answers my question (it is a bit vague).  Will Arlo Pro 2 use my google wifi or will Pro 2 only talk to the base station?  My google wifi most likely has better range with a AP in the front, middle and back of the house.  

(model thingie at the top would not take "vmb4000" but that is the model I see on the website)

[Streak2]

It sets up and manages its own wireless link between the base and the cameras.

The base requires an ethernet connection to your network. 

It should ideally be centrally located in order to create decent signals between itself and all of the cameras.

As you have mentioned there are other features that the base offers like local storage and siren.