Connecting multiple speakers thru wifi

Depends on what you mean by “connect”.  You can group as many as 32 speakers together.  But that is temporary.  For a permanent room, you can have a stereo pair or a soundbar/Amp + surrounds, with or without subwoofer(s).

Looking for a whole house system if I get the ERA 100 how many speakers can I connect to that and scatter through out the house?

You can have 32 Sonos devices total on a system, plus 32 controllers active at the same time. 

ok, so we are clear before i place my order, if i get the ERA 100 2 room, what device (speaker??) do i purchase to extend this to a whole house type set up?  Do i purchase and additional era 100 or is there just a speaker that i can purchase instead of another era 100?

Any Sonos device currently sold can be used in the same multi-room environment.  They all will allow grouping of individual rooms.

So if I purchased the ERA 100 2 room What device do I purchase to make it so I have speakers throughout the house connecting to my ERA 100

As said any other Sonos speaker will Group with your Era-100. 

You just need to purchase the number of Sonos you want and add them to the Era-100’s setup.

You do not need anything else.

Do you have a specific Sonos that would work the best to pair with my ERA 100 to accomplish my whole house effect?  If you were buying this system new, what Sonos would you buy to pair up with my ERA 100 2 room system?

I don’t know how to say it any clearer:  ANY* Sonos device you can purchase will be able to be grouped with any other Sonos device for whole-house audio.  You can group and ungroup to your heart’s content.  Read about it here:

https://support.sonos.com/en-us/article/group-and-ungroup-rooms

You can group them (pairing is something different) with a single Move, all the way up to the Ultimate Arc Immersive Set.

*Note:  Ace headphones can only be connected to a Sonos soundbar for TV sources.

I don’t know how to make this any clearer, I am asking you for advice on your product.  Sorry for not using the correct terminology but I am sure you understand my question.  Do I need to buy multiple ERA 100’s or will the ERA 100-2 room and just buy a speaker only to GROUP.  Your link does not specifically answer my question.

Not sure why you can’t answer my question.  If you owned an ERA 100-2 room what speaker would YOU buy to group, to accomplish a whole house system.