I received my 12’x12’ Gazeebo and set 49 20” patio blocks down. Then set up my Gazeebo. The legs hit almost in the middle of the 4 corner blocks. So I drilled two holes in the blocks corresponding with the bracket on the bottom of the legs. Installed two tap on bolts in each hole’s ( Lift the legs each block is 65 lbs). Then I installed 4 , 15” earth anchors in each corner. 
Last I installed a ratchet strap from the anchor to the top of each leg. Wrapping it over the leg and hooking it on the side bar. Well it has with stood 70mph gusts , a close tornado and three thunder storms so far , without any damage!!! I love it !! We really enjoy our Gazeebo .  I will take it down during the winter though!!