According to the this article ( Hardwire Wifi devices with Ethernet ) you can connect as many as you want.
Keep in mind there is likely going to be a decrease in data speeds the more access points you add, more with wifi than Ethernet, since you are splitting the available bandwidth and/or wifi signal more and more. If you are having connectivity issues due to dead spots, try relocating the devices first to make sure you aren't being affected by obstructions, especially since they have such a large range; Ethernet is always best if possible for that reason. If you are just trying to connect more devices hardwired to the network, invest in a switch and run some cable which I actually did myself.
5 pucks is the max recommended amount if going wireless mesh/ backhaul only.
Also be aware that too many pucks in too tight space will hurt performance due to interference.
More info on this:
Also be sure to not try to mix the new Nest Wifi Pro with older models, as they are not backward compatible.
We appreciate your help here, @olavrb and @PatrickP_Viking.
@Aly283, I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any concerns or questions from here, as I would be happy to take a closer look and assist you further.
Just checking in to make sure that you've seen our responses. Please let me know if you have other questions or concerns as I will be locking this in 24 hours if I won't hear back from you again. Feel free to start a new thread and we'll be happy to help.
I appreciate the help, Mel and Princess.