What is the test for determining that which is in the child's best interest?

Determining that which is in the child's best interest requires that consideration be given to many factors, namely the care and affection shown; the stability of the respective parents; the atmosphere of the homes; the ability and availability of the parents; the morality of the parents; the prospective educational probabilities; the possible effect of custodial change on the children; the financial standing of the parents and the parents' past performance are but a few of the areas requiring exploration. Saunders v. Saunders, 60 AD2d 701, 400 NYS2d 588 (3rd Dep't. 1977).