Kumargi has it nailed - if you are deficient in calcium by all means you should take it but you are high in it then it becomes a nuisance. Do the assessment, it is well worth the $100 - Personally I think Trace Elements is the best test.
Taking the right forms of minerals is important. I do not like oxides, citrates or oratates. I like mag lysinate, glycinate (Doctors Best High Absorption Magnesium) or UltraMag. Mag Chloride can help some and others report issues. Calcium carbonate is horrible, not sure why anyone takes this. I like Source Naturals Cal/Mag Chelate, works well for the calcium.