I have read bundle of burgeoning literatures especially articles, to mention some, Boxall et al. 1984, Citiacy, 1947, Davis (1963), Carson et al 1984, Carson et al 1996, 2001, Adamvoicz et al.,1994, 1996, Hanemann et al1984, and others. Still I have gaps why we choose WTP at anomaly? Contingent valuation preference at the cost of choice modeling is very subjective. There is also a paradox between CVM or CV or CM(CE) technique preference? How Random Utility Model is appropriate to measure individuals preference on non-complementary goods (Private vs Public)? I do have more questions I want to add yet for this time it is enough.