Another way would be to use the Asus RT-N10 routers as 'wireless repeaters' to give better signal. Press the orange button on the back, select repeater, insert same SSID and password as the 'main router' and voila... extra range and coverage at hardly any costs.
I've 3 of these for this job at home and they work fantastically at giving better coverage and have another bonus in that they also allow any wired devices plugged into the routers to gain web access as well (ideal for xboxes and sky boxes
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