Because Codisto LINQ integrates with Amazon & eBay, users will need one or both of those accounts to use Codisto LINQ.
A professional selling account is required to use Codisto LINQ because Individual Sellers are not allowed to use the Amazon API that Codisto LINQ uses. There is a monthly fee of around $40USD per month paid directly to Amazon.
For more information on Amazon Professional selling accounts, see these links for the region you wish to sell in:
Amazon also charges a commission/success fee when an item sells. This varies by category and region. Any fees charged by Amazon are separate and additional to Codisto LINQ.
eBay sellers needs an eBay account registered for selling. eBay fees vary per country for both listing/insertion fees and success/commission fees. Account fees vary depending on country and level of store subscription (useful if you are a volume seller). The following links are for eBay.com but you will be able to find similar pages for your own local eBay marketplace.
Any fees charged by eBay are separate and additional to Codisto LINQ.