Start with the floor plan, not the Wi-Fi generation
A single centrally placed router is often enough for an apartment or compact one-floor home. Mesh earns its extra cost when distance, dense walls, multiple floors, or an inconvenient modem location create repeatable dead zones.
One strong router is the simpler baseline
A single router has fewer radios, power adapters, app settings, and update points to manage. Before buying mesh, test whether moving the router into the open and closer to the center of the home solves the weak-room problem.
Mesh solves distance by adding connection points
Mesh places additional points closer to rooms that a single router cannot reach well. Those points still need a strong path back to the main router; placing a node inside the dead zone can simply repeat a weak connection.
Count wired ports and backhaul options
Some mesh points have Ethernet ports and some do not. Check whether the system supports wired backhaul, whether a switch is needed, and whether the main unit still has enough ports for desktops, TVs, consoles, or a NAS.
Use a two-step buying rule
Try central router placement first. Move to mesh only when the measured weak areas remain and you can place each node where it receives a good connection rather than where the signal has already failed.