家大業大(?)樓上樓下的可以考慮N+AC訊號延伸機
http://www.ampedwireless.com/products/re1900a.html
Amped Wireless Launches Titan-EX Wi-Fi Extender to Obliterate Dead Spots

14000 SQFT = 1300 平方公尺 = 393坪