紧急求助，万分感谢，详见内......

条款内容如下：

Upgrade to “Maple Oxford 3000” iron baluster, flat floor, railing in lieu of standard Maple railing. (Add to Maple flat floor railing price) Notes: Correct amount to be deleted on Purchase Agreement as iron baluster railing was deleted. $ - xxxx.xx

我的理解：该条款包括两部分内容：
第一部分：
Upgrade to “Maple Oxford 3000” iron baluster, flat floor, railing in lieu of standard Maple railing. (Add to Maple flat floor railing price)

表明我们将会得到“Maple Oxford 3000” iron baluster.

第二部分：
Notes: Correct amount to be deleted on Purchase Agreement as iron baluster railing was deleted. $ - xxxx.xx

这仅仅解释为什么给我们$ xxxx.xx credit. 该部分并没有是第一部分失效。

如果要使第一部分失效，应写：
NOT Upgrade to “Maple Oxford 3000” iron baluster, flat floor, railing in lieu of standard Maple railing?

或：

Credit for NOT Upgrade to “Maple Oxford 3000” iron baluster, flat floor, railing in lieu of standard Maple railing......

恳请各位帮忙看看我的理解是否正确？与建筑上发生分歧，心里很不好受。
因为对给条款拿不准，曾至少10次询问销售代表是否将得到铁栏杆，每次他检查该条款，都给了肯定的答复。现在却没有给，难过中......