They have stuff at B&Qwhich is right beside the Ikea out west towards hua qiao cheng area (we took a cab from hua qiao cheng i believe). It's quite massive. Remember seeing quite a bit of outdoor furniture. Not sure how much different prices are from the one in kowloon bay though.

Address for Ikea is below. You can see the big B&H sign nearby since they are all located in the same area.

English :
No. 8188 Beihuan Dadao Nanshan District, Shenzhen (Off of Shahedong Rd. in the European City)
Chinese :
深圳市南山区北环大道8188号 (沙河东路北环大道交界西北角欧洲 内)