Thank you very much for your reply.
I have another question: if the buyers didn't have to pay anything extra for the insurance, how come the Auctiva Checkout confirmation e-mails I received were for a higher amount than the item + shipping?
In one case it was $1.75 more and in another - $2.75 more.
And the question remains, why did I not receive those same notifications when I tried to purchase something from myself?