Reddit mentions of Zyxel 600 Mbps Mini Powerline AV2 Gigabit Adapter, Starter Kit - 2 Units (PLA5205KIT)

^^^pcie*
There are a few options.

1. Use a USB card. They're cheap, universal, and (usually) highly reliable. Just be careful about speed, I once bought an edimax usb card and it was great, but then bought a cheap kootek one and it was actually only capable of around 1mbps
   
2. You can buy a powerline adapter. These let you use your existing power lines as ethernet cables, meaning essentially wherever there's an outlet, you can connect a device to ethernet.
   
3. Just run a really, really, long ethernet cable and staple it to the baseboards. the least likely choice, but i personally don't mind it so i figured i'd throw it in there.
   Keep in mind that you're always gonna get faster speeds with a cable as opposed to wireless.
   Merry Christmas, by the way

I know what you need, you need a WAP that's meant for long distance signals. Ubiquiti has a few that also work outside.

One sec.

Edit:

Since I don't know what kind of ethernet situation you have in the main house, I've included a powerline adapter.

Ubiquiti UAP-AC-LR

https://www.amazon.com/Ubiquiti-UAP-AC-LR-Networks-Enterprise-System/dp/B015PRCBBI

Powerline Adapter

https://www.amazon.com/Zyxel-Powerline-Gigabit-Adapter-Starter/dp/B00D7GF6NA


The way you would set this up:

Router -> Power line #1 -----> Power line #2 (electrical outlet nearest to the wall that's nearest to your house) --> Ubiquiti LR WAP, if you can mount it outside, even better.

Essentially, the powerline adapter will act as an ethernet run for this project, and will allow you to place the WAP on the wall that's nearest to your house from the main property. The LR (long range) WAP that I've chosen should be able to reach your area.

There are more expensive routes to go, but this should get the job done.

Edit:

Or...

https://www.amazon.com/Ubiquiti-PBE-M5-400-2-pack-PowerBeam-AirMAX/dp/B00UZ03UUW

If they don't mind having some little dishes outside.

Make Dad happy. Use an Ethernet over powerline adapter kit. It's plug and play......

https://www.amazon.com/dp/B00D7GF6NA?psc=1

Incredibly easy to set up and affordable. Hope this suits your needs as well as it did mine.

https://www.amazon.com/gp/aw/d/B00D7GF6NA/ref=mh_s9_acsd_newrz_b50jE_c_x_1_w?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=mobile-hybrid-3&pf_rd_r=BCHENZ17DJQXJ06CKJVF&pf_rd_t=30901&pf_rd_p=1429b8ba-e75d-571e-9b71-9f4989516af7&pf_rd_i=1194444

They're devices that you plug into your electric outlet. You plug ethernet in either side and it uses the internal wiring of your electricity system to pass the ethernet traffic.

Something like this.

Two things that may help. One is obvious and free but needs to be stated if we're troubleshooting. The other costs 30 bucks but it totally helped me.

First: UNPLUG ALL THE THINGS! Your router, your modem and your Xbox. Router and Modem are obvious but if your Xbox is set to "Always On" or "Quick Boot" or whatever it's called. The state that allows it to launch quickly when you push the big shiny button on your controller. Change that setting (in your Power menu) and set it to the other option so your Xbox completely shuts down when you turn it off.

It takes longer to power up but it totally helped me with this game, specifically.

Second (and this is a 'not-so-ideal' wifi solution): I'm further away from my router than I would like to be for a strong wifi signal. So I spent 30 bucks on this solution:

https://www.amazon.com/gp/product/B00D7GF6NA/

And it has worked like a charm!

I encourage you to shop around. I'm not pushing Amazon, that's just where I purchased it so it was easy to find the link.

No I haven't, but after doing some research I'm interested. Are there any downsides to doing this?

edit: would this one be sufficient? https://www.amazon.com/Zyxel-Powerline-Gigabit-Adapter-Starter/dp/B00D7GF6NA/ref=cm_cr_arp_d_product_top?ie=UTF8

What was the speed of the powerline adapters? You want to use 500mbps or higher.

The lower speed ones may be older models based on an older version of the "HomePlug AV" standard. You need to make sure you are using one with a newer version of the standard as it will have better error correction and if the line is worse, you will still see better speeds. A crappy line with the 500mbps adapter may still get 100mbps. But if you are starting with a 200mbps adapter, you are going to get much lower.

You will want to use something like:
http://www.amazon.com/TP-LINK-TL-PA6010KIT-Powerline-Adapter-Starter/dp/B00IBPLI48 or
http://www.amazon.com/ZyXEL-Powerline-Gigabit-Adapter-Starter/dp/B00D7GF6NA

The Zyxel is most likely the better option.

You won't get two modems working on one account. That's not how it works. On the other end Cox knows what modem's MAC address is supposed to get service.

Look into powerline ethernet adapters: https://www.amazon.com/gp/product/B00D7GF6NA/

You plug one into the wall near the modem/router downstairs, run a cable to it, and then plug the other one in up in your room and run cables to whatever you're trying to get ethernet on.