谢谢老猫的及时回复，还有一个问题

那就是现在他们批准我们沿着后院的沟建围栏，以解决那里safety issue (信中是这样写的：Council has provided landscaping guidelines which will meet the safety issues of your family, in particular, the ability to put fencing as defined by the guidelines.) 既然fence是建在common property上，解决的是safety issue, 费用是否应该由他们付？非常感谢您专业的意见！