Affixing a Mezuzah to the doorposts of a new home is more than just attaching it and reciting the blessing to abide by
A sofer must qualified to write the prescribed biblical passages, including the Shimah, which is the most important prayer recited in Judaism. Writing the prayers contained in a Mezuzah is no less intricate that writing verses in the Sefer Torah itself, Judaism's most holy written text ; and texts in a Mezuzah that are not certified as being properly written, are not considered as complying with
"Blessed art Thou O Lord, King of the Universe, who has sanctified us with His Commandments, and commanded us to affix the Mezuzah".
Pictured: Ester Shahaf Arch Mezuzah Case
When shopping for a Mezuzah, especially when consecrating a new home, especially for a newly married couple, it is very important to make sure that the words on parchment inside have been written by a trained scribe and certified as being Kosher. Therefore, where the Mezuzah is purchased is very important, as many are sold in souvenir shops, and the "parchment" inside may be merely a photocopy on a heavy grade of paper made to resemble parchment.
The case in which the parchment is to rest is less important though, and many people prefer to purchase the Mezuzah case and parchment separately in order to make sure that the writings are properly certified. Those who are unsure whether their own Mezuzah is 'Kosher' may invite someone from an organization such as Chabad, who will take the scrolls and inspect them for authenticity.
If the scrolls are found not to be Kosher (they may be damaged from moisture, dust, etc.) then for a modest fee they will be exchanged.
The cost of a certified scroll can vary anywhere from $30 to $300 depending on which Sofer scribe wrote the prayers and blessings contained therein. Mezuzah cases can be plain and made of wood, ceramic or plastic material, or very ornate and made from silver and other metals, as well as other ornate materials. However made, and whether they are usually inscribed with the Hebrew letter Shin or the word Shadai, both referring to the Hebrew for