I ordered a KVM from Amazon.com, shipped for free from the United States for ~65USD.
It turned out I didn’t want it, although it’s painless to return an Amazon.SG product, it’s not if it comes from the US.
Free outgoing, not on return
To my surprise I had to pay for shipping back to the US, and it costs about 23USD, about a third of the product’s value.
I complained about the returns experience, but never heard anything.