[B]Option 1.[/B] Try a PowerLine Kit. Go to a local store - so you can return it if it doesn’t work out of the box. The 200mbs varieties are well-tested, the 500s are not - so the well-tested has the best chance of working at better speeds.
If you have a notebook that has an Off-On Switch for wireless, it will be a great tester for you. Turn off it’s wireless, and we’ll go ‘wired’ for this test.
Plug in the Host Powerline into a bare wall-outlet - not to a power strip - and connect the Ethernet into your switch. Then, in the same room, plug in the Receiver unit, and it’s Ethernet will go into your now-certain wireless computer. Power up, and see if you have an Internet connection.
If so, then unplug that computer, take the Receiver unit and take both to the next room. Plug 'em in, and see how that works. Good? Then change floors and see what happens.
You want to ‘stairstep’ your way to your final destination because PowerLines are much like Wireless - there will be a limit of functionality based on wiring, circuit breakers, etc, instead of Lead Shielded Refrigs, Microwaves, etc.
Assuming all goes well, NOW you might decide, “Should I try the more sensitive 500mbs units?” At least with the 200mbs working, your household electricals pass their test. If the 500s fail, it’s THEIR higher intolerance for line-noise on the power-lines.
If the PowerLines don’t work, they will fail to connect. Wait 3-4 minutes, maybe 5 per CONNECT attempt. Normally, even a minute is ‘enough’ but some multi-floor houses do take longer. And then some just never connect.
PowerLines have the nice feature of Working or Not-Working. Settings can sometimes affect speed, but generally not - it’s a “It works” or “It doesn’t” kind of technology.
[B]2. Hardwire the place.[/B] Tell the wife she won the trip to Hawaii. Or at least LaJolla. Coronado may not take enough time! If you can do punch-down plates, she might not even notice!
[B]3. Antennas.[/B] You’re probably looking at range-extenders, which means finding those with a cooperative radio-chip like your wireless units have. What a pain. Then there’s all the security settings - take those off, first, and then install all the range-extenders, get the sub-nets and gateways matching, etc. Get the connections. Now, set back up security, one by one. Yawn. Hand me the drill…I’d rather do punch-downs and drillings…