You can update your listing using CSV files.
In your CSV file, you should have a column titled 'sku' and a column for each field you want to update.
If for example, you want to update the price and the stock of the SKU sku_1 and to update the price of the SKU sku_2, your CSV file should have this form:
Among the fields you can change, there are:
- the price
- the quantity
- the warranty delay
- the comment
- the shipper
- the shipping delay
- the shipping price
Once your CSV file is ready to be imported, go in your Back Office on the 'Offer' tab and click on: 'Offer update (stock/price)' and upload your file.
For European sellers only (or US Sellers selling in Europe): if you want to have your listing listed in several countries, you can read the article How to put my listing live in other countries?