For several years I've successfully used a stock Linksys WRT1900ACS v.1 router for my 2400 sf home, with a Linksys range extender and guest network mainly used in a small (240 sf) guest cottage about 30 ft. from the main house. But during the COVID period I've received complaints about the network being very slow in the cottage.
So I purchased a Linksys WRT3200ACM router, planning to move the 1900 to a bedroom in the main house much closer to the cottage and use it to boost the signal in the cottage. The 3200 would take over as the master router, and the 1900 would connect to it via ethernet cable, as the house is wired for LAN.
My plan was to bring up the system using stock Linksys firmware and then switch over to OpenWrt to gain more control and boost the signals. But I've run into trouble with the Linksys routers. If I correctly understand the Linksys tech support agent's explanation, in bridge mode the routers don't support guest networks, and as access points they are essentially independent routers that simply run their own, independent networks. In contrast, I would prefer to seamlessly extend the reach of the two private network channels (2.4 GHz & 5 GHz) and the single 2.4 GHz guest network on the 3200.
Today I spent almost 4 hrs. on the phone with Linksys tech support, mainly because the 1900 had connectivity issues after I reconfigured it according to the support agent's instructions. But this has me wondering. It seems even after we solve the connectivity issue, the stock Linksys firmware still won't provide the kind of system I need. It makes me wonder if it's worth the effort just to implement an unsatisfactory architecture.
This leads to my question(s). First, stepping back to look at the overall problem, what's the best way to improve the the guest network's performance in the guest cottage? Second, assuming the second (WRT1900ACS) router plays a major role in the solution, exactly how should it do so? Third, can OpenWrt provide a more satisfactory solution than the stock Linksys firmware can? How?
Fourth, a more general question: if one's WiFi network is down while installing and configuring OpenWrt, how should one follow the instructions?
While I'm rather skilled at general computing, with networking I'm at most at an "intermediate" level. With OpenWrt, or any form of third-party firmware, I'm a rank novice. So please answer at a suitable level ("OpenWrt Guest Networks for Almost Dummies").