I wouldn't recommend an 'extender' unless you absolutely need it. (And, certainly not before you've tried the suggestions below).
First, I would suggest the RT-AX68U, GT-AX6000, or RT-AX88U Pro (the latter, only if cheaper in your area and you are prepared to test and return it if not stable in your setup).
Ideally placed, any of the above routers should give you a significant upgrade to your network and better match your current ISP speeds. The GT-AX6000 is usually the least expensive option (when on sale) and will offer you the highest performance for the least cost. Backed up by known stability and reliability (for the past year or so). To me, the RT-AX88U Pro is unknown. It is still in its teething phase. But it may become a good/great Asus/RMerlin-powered router too (in a few month's time). The RT-AX68U is the minimum I would recommend for your network and current ISP speeds, and will also greatly increase your network's performance with higher throughput and lower latency throughout.
With any of these routers, you will have access to the latest firmware level (3.0.0.6.xxx) and therefore expect support for a good long time.
You may also see that an extender is not needed in your home either with these models. Provided you optimally place it and set it up properly too.
The links below may be helpful to get your network running smoothly and as stable as possible.
I have an ASUS AX86U and contemplating the installation of Merlin firmware. The DDNS settings on the AX86U are limited to select dns providers. If I install Merlin, will I have more flexability (choices) with the DDNS Settings? Thanks in advance!
www.snbforums.com
After creating the checklists two weeks ago to save the pages with settings, I've made all the screenshots (I think at least) of all the relevant guides written by @L&LD and the very useful tip by @netware5. The only thing is, those guides are great, except when you'll be offline at least for a...
www.snbforums.com
www.snbforums.com