Like apple products, the whole catch is to buy more and more. It's only good as how many you have.
3 pack sounds like a lot, but it's pointless unless u go for 6. 1 = hub connected, then u need 1 near the hub regardless (which is pointless because the strongest signal is already happens when you are near the router/modem regardless of the eero. Then you have 1 final eero really for wherever you want it. So really, now your about 30-70 feet away from your modem. I have (2) 3 packs, 6 total individual eeros, thus maximizing its full potential after sacrificing like 3 eeros in my 3800 sq feet house. But yes, it would work 40 feet from the house if you set it up linear with a 3 pack. But would you waste eeros like that? Actually you can move them anywhere when you aren't at your pool.