There is a main house and a guest house about 1000 feet apart. Comcast is hard wired into both houses (same account). There is only internet service (no phone or cable TV). I rent the guest house and need wireless internet. Right now there is a cable coming out of the wall with what appears to be a coax thing at one end and an Ethernet thing at the other end, which I can plug into my laptop. (I hope this makes sense, I'm not very technical.) I know there is a modem/router in the main house but I don't have access to it. How do I install a wireless router in the guesthouse that won't interfere with whatever is going on in the main house? Thank you!