You agreed a price and the buyer is waiting. Here is the practical part. Packaging. A padded envelope is enough for a single paperback. For hardbacks or several books, use a small cardboard box and fill the gaps so the corners do not get crushed. Posting. POST Luxembourg counters are in most communes and in many supermarkets. A standard national parcel arrives the next working day in most cases. Cost. Agree who pays before you send. Many sellers simply include shipping in the price, which makes the listing easier to compare. Proof. Keep the receipt until the buyer confirms the book arrived. It costs nothing and settles any disagreement quickly.