Using the WDS (wireless bridging) feature of this WAP, is it possible to set up a relay WAP connected to two other WAPs (one on either end) so that I can connect devices at a longer distance than WiFi would reach in one hop? I'm slightly confused about the language in How do I set up a wireless bridge (WDS) on my WAC505, WAC510, WAC540, or WAX610 access point? - NETG... where it says "The WAC510, WAC540, WAX610, and WAX610Y wireless access points also support point-to-multi-point configuration. This allows one base access point to connect to four remote access points independently". In my scenario, the access point in the middle (having two WDS end points) is NOT acting as a base and I'm not sure how packets would be routed?
There is no daisy chaining possible on a WDS system. Either way, in point to point or in point to multipoint, in case you go and test with a daisy chain of multiple AP, you will realize that all APs must be operated on the same channel or channel-sets, means the performance is halved on two WDS, and about 1/4 if testing - or worse, in reality much worse.
Essentially the same limitations apply to deploying multiple wireless extenders in a daisy chain config.
The only technically feasible path with WDS would be to build two independent WDS systems, with two plus two APs, operating on different (fully independent) channels, connecting the to WDS systems by an Ethernet cable.
More complex designs could be done with the Insight Instant Mesh. If it should perform well and provide availability, I strongly suggest to deploy two or more so called root-AP in an all-wired configuration, and place some wireless satellites around these root-APs within WiFi reach. Granted, Netgear often shows examples of a wireless Mesh backhaul, so watch your steps, or start building your own expertise and experience.
WiFi can perform well if all end points logically can "see" each other, very similar to Ethernet Carrier Sense Multiple Access/Collision Detection (CSMA/CD). What is clear on a healthy wired network requires some workarounds using certain tricks for WiFi - with longer random delays than on the CD method.
Said all this: There is no el-cheepo option possible.
