Excel Spreadsheet assistance picklist data -- 2

We are looking to use this drop-down asset checker for our install team - ideally, we would like the list part of the excel sheet to disappear as it gets selected so that there are no dangers of duplication. We would also like to investigate the idea of scanning in barcodes and pictures from an iPad into the excel spreadsheet (these last two asks are long shots - the first part is the major requirement)