Buy it for Life

This kind of tech stuff isn't really BIFL. However, you can extend the life of it by separating the components. So an OPNsense box for the firewall/gateway (this can last many years with very little maintenance), a separate WiFi access point (AP), and a switch.

Many consumer-grade Wi-Fi routers are all three of these components combined into one (usually) low-quality package. When one part of it dies or becomes obsolete, the whole unit would need to be replaced.

By separating the components, you can get better quality hardware (even if consumer-grade), and replace/upgrade them independently when needed.

In tech, nothing is for life.

But, I would recommend something you can install OpenWRT or OpenSense. If sorting out hardware isn't for you, I have a Ubiquity UDM Pro and love it. I miss some of the fine tuning of OpenWRT, but the extra security features on the UDM seem worth it to me.

Probably better to run a cable to have a router on both sides of the house. Wifi extenders are notoriously unreliable.

Your biggest worry with something that’s connected to the internet are security updates and in general nobody will support a product indefinitely so can’t really buy anything for life. Your best bet would be a router that supports open firmware like OpenWrt.

Probably not your router, but Flint 2 is the way to go. Or preorder a Flint 3.

are you sure it's a LAN issue rather than a problem with your ISP?

The problem with for life products in this segment is that technical advancements come quickly and make old stuff obsolete not due to breakage but because your requirements might have changed beyond what you have now.

That said I am somewhat content with my Fritzbox 4790. It's still getting regular updates. Same thing with my Ubiquity wifi access points.

But I sometimes would like to have the peace of mind of OpenWRT compatibility.

I'm a big fan of mikrotik: Simple no bullshit devices, and OpenWrt is support on most of them, see https://toh.openwrt.org/

I've been using Linksys E4200's with (Fresh)Tomato firmware for about 10 years now. Recently one failed and I think, due to all the claims about new wifi "versions", the more modern devices should provide better performance, so I've been reading some stuff every now and then and looking for a new setup.

People with knowledge (tm) who I semi-trust all seem to point at different devices for the wired and wireless part. Some even say you should split the router from the switch (so you can do a managed switch with vlans and stuff) but I will never use any of that and even my E4200's can handle vlans just fine. I do get that using dedicated access points has its advantages but it does get quite a bit more expensive.

On the other end, a lot of brand names are now using Chinese chips in their routers and devices like the GL.iNet MT6000 seem to be one of the current favorites on the openwrt forums (and seems to be a very powerful device). I think I'm still going to go for a separated setup but I've got no clue which devices yet.

Fwiw, Louis Rossmann recommends some things.

Hi, depends of your knowledge level I can suggest you 2 alternatives.

If you are tech savvy I recommend you to setup your own router and then install something like opnsense, then you can use wifi extenders to make sure you reach all the corners. For the hw there are a lot of router boxes in Amazon for 200€ with powerful cpus and 16 gb ram that should be future proof for the following 15 years. Opnsense (for the Sw) also has a very long record of supporting x86 architecture for ages.

In case you are more limited kn tech skills try to get a top of art router from a reputable manufacturer and make sure you can install openwrt on it. Openwrt is more limited speaking about features but it is a more router oriented Sw which can be easily understood. It also has a good record of supporting legacy hw.

As somebody else suggested, the obsolescence of the electronics is more related with the Sw and regulars updates than the hw itself. A good made hw can last >25 years without any probelm. Assuming that the performance is still good for your needs.

Setup a mesh network with multiple OpenWRT devices

For life is tricky considering "end of life" products will typically still work reasonably well for decades after being obsolete, but might be susceptible to future exploits that end up unpatched, and you really don't want to become part of a botnet.

With that said, I've had an Asus RT-AX88U for over 6 years now, it's receiving regular updates, and there's a third party firmware (Merlin) that adds some features and keeps being upgraded as well.

My house is 20m square, but I have a shed outside with some gardening automation going on, so overall it stretches 34m from router to last device. I have two Asus Zenwifi AX mini mesh-nodes, one upstairs and one in the rear end of the house (about 18m from the router and 14m from the last device), and I don't have any connectivity issues.

Overall there are 22 devices permanently connected, plus another 4-6 randomly (two laptops, 2 phones, plus visitors).

Never had an unscheduled reboot, though I do install new firmware every 2 months which takes the network down for about 5 min.

Definitely recommend Ubiquiti Unifi products. Very reliable and easy to use.