Extending wireless internet signal?

[johnathon r]

I am trying to extend my wireless internet range so that my sister who lives on the same property but about 3-400 feet away can share my internet. I currently have a Netgear N600 router which has no external antennas on it here at my house...She can not get online as the signal is can not reach. I cant even access my router on my phone when im in her house. I am wondering how can i extend my range. Do i need to buy a new router for here at my house, possibly one with antennas on it? Running a cat 5 cable from house to house is a hassle as the only person that can do it seems to never have the time and i can not physically do it, because of being wheelchair bound. We both have metal roofs on our homes but i was told that wouldnt make much of a difference. Any concrete advice would be appreciated. please no BS answers. Need to get this done as soon as possible.
I repeat, i am trying to get this done as soon as possible and running cat 5 or cat 6 cable from house to house would take to long due to no time for the only person that can physically do it.

[Jan]

What you could do is put an ethernet cable (cat5e or cat6) from your wireless router to where she wants internet. You can run a network cable for 150m (450ft) without too much degradation. Then connect it to a new access point you'll have to buy (check amazon).
That way you can share the internet connection without too much hassle.

[John W]

There are WiFi repeaters that you plug into a wall outlet just at the outer reaches of your signal but they tend to be expensive and often do not support encrypted cells. If your house is prewired with cat 5 or cat 6 which many are now, you can run a line and use another base station on another channel but using the same SSID.

[Comicbook Reader]

The single easiest method is to buy a wireless extender. There are some good, cost effective brands on the market and easy to setup. The Amped will throw the signal a couple thousand feet.

[Duncan]

So... on the same property but in another building?

You are unlikely to get satisfactory results with a wireless connection over such a distance from building to building as it will be subject to all manner of interference.