We need to replace our router now that we move.
Which one is a good one-device-router that can handle a smart home with lots of wireless devices?
I don’t believe there will be a need for a mesh since I believe one well placed router will cover the whole apartment.
It’s hard to find any information about how many devices the routers can handle. Anyone know a good source for that information?
I am confused. Are you talking about a router or an access point?
Router with wireless access point.
Not a mesh style, and not a ubiquiti style where you have router and access point separate.
I don’t use a proprietary router, as most are underpowered rubbish that can’t handle more than 20 connections. Instead, I have an old computer running open source software, OPNsense, as the router/DHCP server/firewall and a separate wifi access point.
No brand name router/access point can compare in speed and quality.
OPNsense is easy to install, manage, and has anti-virus plugins. As it can run thousands of connections, it suits my home just fine. 
Yes, there is no room for something like that.
And this is not the time to start to build something, we need something that works when we move.
Perhaps some other day.
I have around 50 connected devices, with many own build ESP switches and sensors and also Yeelights and a Xiaomi hub. I upgraded from an ISP provided (U.K.) modem/router just over a month ago. As Tromperie said, it was underpowered and every few days I would either lose the 2.4 GHz band or experience drop outs from various devices.
After reading loads of reviews, I settled on a TP-Link Archer VR2800. It consistently came out at, or near the top of everything I read. It has the added bonus for me of a DSL modem built in as well, so no need for a second box. It does not have WiFi 6, but I have mostly legacy devices which I do not intend to upgrade unless they fail, so this was not an issue for me.
It’s now been in service for over a month and I have not had a single outage or device drop out. It was very easy to set up, runs cool and all the menus are lightning fast. I’ve set up the built in open VPN server so no longer need to run that on a separate device for access to the home network while out and about.
I might also concur @MartinB on using TP-Link devices. Before going into Ubiquiti path, i used TP-Link devices for years and they never let me down.
Thank you for the advice about tp-link @MartinB .
I have looked at some tp-link devices but not this one in particular.
I read some reviews and comparisons of mesh routers (I know, hear me out) and Asus ZenWifi XT8 has gotten good reviews.
I figured I could buy one of these, that means i get a good router and could use the backhaul channel.
And today they are on 90 euro discount.
That seems like a good deal.