There are three ways of identifying a qualified mujtahid but knowing only that somone is a marji‘ or hav a book on practical laws of Islam is not the proper conditions for taqlīd of a qualified mujtahid.
question: Is it permissible to follow a mujtahid who is not a marji‘ and does not have a book on practical laws?
Answer: There are three ways of identifying a Mujtahid, and the A'alam, the qualified mujtahid:
1. when a person is certain that a particular person is a Mujtahid, or the most learned one. For this, he should be a learned person himself, and should possess the capacity to identify a Mujtahid or an A'alam; 2. when two persons, who are learned and just and possess the capacity to identify a Mujtahid or the A'alam, confirm that a person is a Mujtahid or an A'lam, provided that two other learned and just persons do not contradict them. In fact, being a Mujt ahid or an A'lam can also be established by a statement of only one trusted and reliable person; 3. when a number of learned persons who possess the capacity to identify a Mujtahid or an A'lam, certify that a particular person is a Mujtahid or an A'lam, provided that one is satisfied by their statement.[1] If it is proven for a mukallaf, who wants to follow this mujtahid, that he is a qualified mujtahid, there will be no problem in following him. In other words, being a marji‘ or having a book on practical laws of Islam are not conditions for the taqlīd of a qualified mujtahid to be correct.[2]
1. Ayatollah Seyyed Ali Sistani , Islamic Laws Following a mujtahid (Taqlid)11..
2. Ayatollah Seyyed Ali Khamenei, Practical Laws of Islam, Rules of Taqlīd, Conditions of Taqlīd, Q9.