Does happiness come with a price tag?

Does happiness come with an expiry date?? Why is it only periodic? It is like medicine that when the dosage exceeds the limit we are prescribed or maybe, when we are cured (from the monetary dullness and regularity of life)that we need to stop..why is it like a flimsy mirage? elusive..always..just when we think we have it in our grasp, it slips away like silken threads from our fingers? Is it because we materialize, label and try to purchase happiness? So that the more we try, the more elusive it becomes? I have always believed that the pursuit of happiness is best traveled inwards..our innermost being..that is one thing very much within our capacity to fulfill rather than scaling mountains, scourging oceans...braving windy bellows...to find that place where we are united with happiness...however, these past few days (been quite sometime now), am starting to doubt the truth in this. If it is so within our reach, camouflaged in our being..why is it the toughest to locate? after-all, end of the day, we earn, we eat, we fight, we cry, we grieve..isn't it not only for attaining that one moment of true happiness...just a thought!