But repeaters in all cases reduce speeds. Cables are still the cheapest way to connect at full speed.

"some of you maybe wondering why dont i just connect my server and roku directly to my main router, well its because it aint actually my router, its my landlords, i just set it up for him and its located in his room. im just renting a room, so I cant have ethernet cables running from my room to his, so im stuck using wireless, at least between the main router and me."

Then you want your own LAN. Simple really. Use a WiFi client to receive the internet from where ever and that can go to your own router either as a WAP (see google, router as a wap) or try it to the WAN port.

Now with that you have your own high speed LAN.
Bob