@randomName what are your ISP speeds? What is the construction of your home? How well does your current RT-AC86U cover it?
Forget about using a 'repeater'. That will worsen your WiFi experience if the repeater is heavily used (as I assume it would be).
Depending on your specific environment, 5000SqFt coverage
is possible with a single router even from 2016.
RT-AC3100 Report https://www.snbforums.com/threads/s...-go-with-the-rt-ac1900p-v3.34748/#post-281391
If you were to add a second RT-AC86U to your network in AiMesh mode you should see very good coverage from that simple upgrade, assuming that the single RT-AC86U is currently just shy of providing the coverage you require.
Going to the RT-AX88U, you should be seeing an even bigger jump (but I would be using the 'AX88U as the main router and your existing RT-AC86U as the AiMesh node) in network performance.
A possible 'in-between' step to the next option may be an RT-AX88U and an RT-AX58U to be used as an AiMesh node (if needed). Sell the RT-AC86U and upgrade your entire network to 'AX for almost 'just' the cost of an RT-AX88U.
With 2x RT-AX88U's (in a
wired AiMesh setup, if possible) you should be seeing the best possible throughput, stability, reliability and coverage of your home. If needed, you can still add the current RT-AC86U to light up specific areas too (i.e. the back garden). Or, go 'AX all the way and add an RT-AX58U here too (again; only if needed).
Even the single RT-AX88U used as the main router will give you further benefits over an additional RT-AC86U.
- Twice the RAM.
- Twice the cores (useful for scripts, multiple OpenVPN connections, etc.).
- Observed better throughput at equal or greater range.
- 4x external antennae (vs a 'hidden' one in the 'AC86U).
HTH.
