When listing all products, you must request it on a page by page basis, as such the limit is 100 products per page as is the case within the UI. If you know how many pages of products you are expecting however, you could make consecutive requests, increasing the page number each time and fill your data file that way.
With regards to the product properties fields - all available details which are viewable from within the API are documented here: API Docs - Veeqo Developers