I started performing Shiva pooja of the family pooja which was carried forward from great-grand father to grand father to father to mother and now me. Are there any experts, priests who can see defects in the Shiva linga, Shaligram and other idols which may bring negative energies?
For the time being a partial answer.
For an idol (Vigraha), the defects are presence of holes in it, broken, lacking in limbs etc.
In the Mahanirvana Tantram's Chapter 14 Lord Sadashiva enumerates these defects:
The wise man should not worship the image of a Deva which is broken or is holed, or which has lost a limb, or has been touched by a leper, or has fallen on unholy ground (100). The image of a Deva with missing limbs, or which is broken or has holes in it, should be consigned to water. If the image has been made impure by touch, it should be consecrated, and then worshipped (101). The Mahapithas and Anadi-lingas are free from all deficiencies, and these should always be worshipped for the attainment of happiness by each worshipper as he pleases (102).
I will update regarding defective Shiva Lingas later.