Am I sinful or mistaken for not paying the delivery costs of the bedroom set that I refused to buy, after it became clear that it was more expensive than I had thought, and the saleswoman had previously mistreated me?

The sale is void if the buyer was unable to see the bedroom set or if it was not described sufficiently to prevent dispute. This is because one of the conditions for a valid sale is that the object of sale must be known to both contracting parties. Therefore, the seller reclaims her bedroom set, and the buyer receives back the amount paid. What the owner of the bedroom set demanded regarding the cost of transporting the set is not binding upon the buyer to pay.