Hi,
What solution are they using at the moment ? How many products / orders do you have in each one ?
If they use VirtueMart, there is an import tool in HikaShop.
Otherwise, it would probably require a custom script to be developed for each ecommerce solution. This can be tricky. It can range from a few hours of development to weeks of development, so it can quickly add up. In that case, using the services of
litextension.com
to migrate from the existing solution to HikaShop will usually be way cheaper but we got feedback that sometimes it can leave a bit of a mess to be cleaned up after the migration.