Dynamic Data Validation Dropdowns Problem

Not even sure if what I am trying to do is possible, but here goes.

I need to setup a dropdown list (I already have the dropdown created) so that once a value in the list is used, it disappears from the list. Now for the monkey wrench...It need to completely re-populate once the list that is being generated from it is cleared.

I also need to copy a value from one sheet to another sheet, however, the location needs to be matched with a corresponding value from the first sheet. Hopefully it will be easier to understand within the workbook (I feel like I'm not explaining it well).

I have attached a sample copy of the workbook and what I am trying to accomplish.

Mens_Dorm_Sample.xlsm

Works Perfectly!

Thanks, brokenbiscuits!