Does Rivly use flat files or spreadsheets to create and edit listings?

Yes, we have a bulk file (or flat file) system to allow bulk changes to listings or import listings from most other marketplaces. That being said, something we’ve really tried to make easy is the ability to make bulk changes WITHOUT the use of a spreadsheet using our Bulk Actions on the product list: change price, close listings, change category, create or add new variation families, and so much more.