Home Fiber Kit: Wired Internet Where You Need It – Create a Nearly Invisible Wired Connection for Wi-Fi, Gaming, and More – Ultra-Thin 0.6mm Fiber, DIY Installation, Up to 1Gbps Speed

https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V

How about something like this? https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V It's not clear how your roomie needs to connect to the router. I've never heard of a coax connection for anything but a TV signal, or that janky MoCa network stuff.

They make kits as well with fiber already terminted and spooled to hold the excess wire. https://a.co/d/0iAKpPqr

anything you do will be severely limited by the wall. an no wireless mesh setup will preform the way a wire currently does. you have a hole, just run a wire. my recommendation for making is basically invisible is one of these super thin fiber kits.https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V this will lets you have a wire, but you can easily run it diagonally to the black wall then run it upwards(or downwards) in the corner, then use some filler and paint to cover the hole and i grantee you if you spend a bit of time then noone is gonna be able to tell unless your specifically looking for it. here is a demo video: https://www.youtube.com/watch?v=Z2FbzCyiNr4

Try this. https://a.co/d/01qxHqdhAn ultra thin fiber kit that’s virtually invisible when installed.

Should work fine. Is the GF going to be okay with bright yellow cables? If not, consider this kit, replacing everything you’ve selected: https://a.co/d/0jleyhDb

Have you thought about fiber? https://a.co/d/0bBLad60

HERE is an example. HERE they are on Amazon. The hardest part is finding a good path to go. If you have to go across the floor, like where your office door at is, so a search on Amazon for "cable management across floor" You'll find a few things that would do the trick. Protect the fiber, not look bad and temporary for a renter.

There are basically invisible fiber kits, but they’re expensive and and limited length. https://a.co/d/08DtVWo3

another option is to run nearly invisible fiber along the baseboards and door jams. put media converters on each end. you can use glue to attach the fiber cable. here is a complete kit https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V although, you should be able to put together your own kit for much cheaper. 2 of these https://www.amazon.com/TP-Link-Ethernet-Converter-Supporting-MC220L/dp/B003CFATL0 2 of these https://www.amazon.com/TP-Link-1000Base-LX-Single-Mode-Interface-Distance/dp/B003CFATYW/139-0294506-9449455 and a premade fiber cable the length that your need. note that you can always curl up the excess at the ends. also, fiber is an excellent surge protection as power/energy cannot travel through glass.

The fiber in the InvisiLight kit tolerates a 2.5mm bend radius. I’ve not been able to find comparable fiber sold separately at any price. The fiber itself will easily support 10Gbps and faster; you’d just need to replace the stuff on the end.

Invisilight https://a.co/d/08ppHnQq

Too many APs is also bad. If you happen to get decent signal from the other room, your device might hang on to that connection longer than it should, giving you a relatively poor connection. It really depends on how much the signal is blocked by the walls. My parents' house has some thick/double-brick interior walls, so I am aware of how much that can kill a Wi-Fi signal. It would be best if you could install one AP first and see how it does, then add another if needed. How close are the offices? I was picturing them right next to each other, but it looks like you didn't actually say that. Depending on the layout, you might be able to use "invisible fiber" to link them and get Ethernet in Office 2 as well. https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V/ is the all-in-one premade kit, but you can buy the components to DIY the same sort of system. Run Ethernet into one media converter, transparent fiber comes out and is routed to the other room, fiber goes into the second media converter, and Ethernet comes out. https://www.amazon.com/dp/B0F9HQS9SN/ is the cable with LC connectors installed. https://www.amazon.com/dp/B09Q81KLRP/ is a pair of 1Gb media converters with LC SFP modules. If you need a switch in each room anyway, you could get a couple https://www.amazon.com/dp/B0G19C3F48/ and plug https://www.amazon.com/dp/B0DPG4RK8F/ into them (instead of using the pair of media converters). https://www.amazon.com/dp/B01LWA648H/ is the 10Gb SFP+ version, if you wanted to spend more and get a faster link between the switches. This invisible fiber might even work for wiring up other areas of the house too, and save you some cable-running effort.

https://www.amazon.com/dp/B0F8DQW36V

In your case cat5e is the minimum you want, and anything over cat6a is going to be overkill. Tbf anything beyond cat5e is going to be overkill unless you have 10Gb networking. https://en.wikipedia.org/wiki/Category_5_cable There are also products like this which use fiber, https://www.amazon.com/InvisiLight-Home-Fiber-Kit-Installation/dp/B0F8DQW36V But the cost is pretty damn high when $50 USD of ethernet could accomplish the same thing. Also make sure to accurately measure how much cable you need, and then get 10ft more than what you measured. You want to have some extra slack on the cable at the ends so you can move things around without pulling on the wire.

Apalrd's Adventures on YouTube made a video about something very similar a while back: https://www.youtube.com/watch?v=Z2FbzCyiNr4 Not sure if this is the same product you are talking about, but they are available (at least in the US): https://lightera.com/invisilight-home-fiber-kit/ https://www.amazon.com/dp/B0F8DQW36V?ref=myi_il_dp

As I said, the lease only prohibits making holes, it doesn't prevent you from doing so if you're willing to live with the consequences. It might also be possible to use a ultra-thin fiber optic kit (or its component parts, which would be less expensive), to glue fiber to the baseboard and wall moldings between rooms. I have no experience, so I don't know what it actually looks like when installed. But free Amazon returns if it doesn't work out.