I have a customer that wants to archive certain folders/tags on a regular basis when hes finished with a client.  Hes currently using Google Workspace via a browser.  He wants to export them to some sort of easily readable format and store them in Dropbox.  I have suggested running Outlook and exporting the particular folders as a PST but hes not too keen on that. 

I have found a Chrome plugin which will do it: CloudHQ Export Emails to Google Docs.  This does exactly what he wants (except moving them to Dropbox automatically). It saves the emails as a PDF and the attachments alongside them into Google Drive as well as making a Google Doc with all the emails in it.  Hes not overly fond of the pricing though ($150/US a year) as hes not sure how often he will use it.  

Does anyone have any suggestions/solutions that would cost less but still do a good job?  Generally speaking hes wanting to export around 100-200 emails at a time so doing it one by one is out of the question. 

I know I could also do this in Thunderbird but Im not sure if hes too keen on that either.