Copying files, verifying and then zipping with a shell script

I am looking to create a script - a linux or a python scrip so that it can create the following things for me as well as Verify the files for me which are copied from a folder. I Have two folders: FolderA has 300 .xls files - This folder is missing some files which are in folder B currently. FolderB has 500 .xls files I want to copy select few 100 files from Folder B to folder A. Then want the script to verify that all the files currently residing now in folder A(should be 400 now after copying 100 files from B) also exist in folder B. Then I want the script to zip all these files separately as its own bzip2 file. Basically there will be 400 bzip2 files(one for each excel) in the end when the process is completed.