I'm using a 3-unit eero setup for a 5,500 sq ft home with 2 floors.  Works well.  I have the 3 eeros placed to optimize the spaces where we use wifi devices most often - cell phones, iPads and 3 AppleTVs.  Hoping to make the best use of wifi bandwidth, all 3 eeros are connected by ethernet. My thinking was to use ethernet for the "backhaul" and let the wifi devices have all of the available bandwidth.

I originally planned to wire the AppleTVs to ethernet, but so far they are working well using wifi connections.  

You might try the 3-eero package for your 5,000 sq foot home.  You can always add more eeros if needed. 

I have a 4800 sq ft home on 2 floors excluding the garage which I have Wi-Fi sprinkler in so I probably surpass 5000 with this.  Anyway, I have 3 eero units and have roughly 23 devices connected at all times.  I have had really exceptional coverage.  I used this to replace a router, extender, and power line interfaces. I do a lot of home automation and also have Plex to distribute movies throughout the house.  I have one area that is occasionally sluggish but no enough to justify another device and not frequent enough to do anything about it.

It was well worth the investment.  Now I need to figure out what to do with the equipment I purchased trying to find a solution.  Perhaps Eero will buy them from us and see how large of a pile they can send to recycle 😉.

So I agree with the above suggestion of 3 and you may need more if you exceed 30 devices or so not sure what a reasonable limit is.  Note the connections are Wi-Fi connections and not any you have set up directly to an ethernet cable.

I would think, like anything wifi the environmental specifics of your location are going to dictate what works or doesn't work.  I will add that my parents home has been particularly tricky, we've tried several configurations and different devices without much luck.  All the other products ended up being flaky or too complex for them to manage.  A few months ago I replaced their last network with Eero and it's worked great.  One in the middle of the basement, two on the first floor, about 1/3 of the way of the house away from the center and one on the second floor (two floors from the basement) roughly straight above the basement eero.  So far everything has been seamless.  I also like that I can see the network health from my app.  

They like to spend a lot of time in the back yard so we added a fourth for Christmas which ensures full coverage out there.

6 eeros. One story, 3200 square feet. Very inconsistent speeds throughout the house. 

Im paying Xfinity for 150mbps. Im getting 50 on some areas. Not happy.

Nicolasmora 6 eeros seems a bit much for that 3200 sq ft. - my suggestion is to try using 4 or 5 eeros placed properly. Sometimes too many units placed too close to each other can cause unnecessary unit-to-unit chatter.

Jeff C.  So I currently have 5 eero in my home. Cable modem is located in a closet in the center of the home but towards the front side of the home. The house is 5000sq ft on a single story. I have a wireless sprinkler system so one unit is in the garage. The eero looks like it should be within 40 ft of each other, correct? Because My home is wide and long on a single story, I feel like I could still use three more units. The reason I think this is even though I have full bars on my wifi connected device ( that is an iPad at the furthest from the center modem eero) the speed is slow... 

Any thoughts?

Also noticed that the IPad is connected 2.5ghz

It sounds like you could use an additional unit.  I have concluded that I do as well.  I may make the comment that will or will not be accepted well.  I have been hesitant to purchase one due to the price.  I do not need three and that is a reasonable cost point.  Can you not provide additional units to verified customers at a more reasonable price?  That or does someone want to split a 3 pack?  I had a price on Amazon for 1 at 104 but the order was canceled due to technical issues.

You are connecting a 2.4 due to the fact the signal is not strong enough to make a 5 connection most likely.  Does it improve if you move closer to the unit?