I'm going to disagree with TechJunky on this one. I've used the multiple AP method previously and while it "works" it's just not as seamless for several reasons which I'll get to. I tried multiple APs to keep the cost down since I already had them, or could get them rather cheap. I tried using different SSIDs and the same SSID. Mesh systems are not "marketing".
Downside to using multiple APs:
1. You have to configure 2 devices, and configure each differently.
2. Hand offs from one device to the other are not that quick, if you get handed off at all. So if you have one device downstairs at the other end of the house and are connected to it you will stay connected to that device even when you go far away from that device and could be right next to the other device.
3. You might need multiple logins and/or apps to configure both devices.
I've had two different mesh systems, the AmplifiHD by Ubiquity, and the TP-Link AX3000 (X55). I use the Ethernet backhaul option to connect the two devices. I'm only using 2 at my house (2600 sq. ft, two story) as that covers everywhere I need access. I have also installed an AX3000 (X55) mesh system at my in-laws and use all 3 devices without ethernet backhaul. Their house is smaller but there's one device installed in a shed out back. The AmplifiHD was nice, but each router cost more than the entire TP Link system. There were a couple of features that I liked about it better than the TP Link, but unfortunately 1 of the routers crapped out and they have been out of stock for a while. So I switched to the TP Link a couple of years ago. The AmplifiHD system had a better way to configure Parental Controls. I could set on and off times per device without paying any fees. TP Link requires you to pay a service fee for this, which in my opinion is BS. They do offer other features with this service, but if all you want is to set on/off times you should be able to do that within the device's settings without paying fees. Other than that the system has been great. We get full WIFi signal throughout the house with very little drop in speed as you move away from one device or the other. We have several smart devices (light switches and such) that never show any signs of being disconnected. Handoffs from one device to the other are quick and really go unnoticed.
I bought mine from Best Buy as I wanted it right away when the other system crapped out. I got this one
https://www.bestbuy.com/site/tp-lin...-gigabit-speeds-white/6479600.p?skuId=6479600. But Amazon has this one
https://www.amazon.com/gp/product/B09PRB1MZM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 which is essentially the same thing, but offers an additional ethernet port on each device which is nice and is cheaper than the one at Best Buy.