The difference between product's value and offer's value

We have the following formula of value:

Value = Benefit – Expenses

But why do we value so much the objects which were extremely hard to receive or which cost so much?

We value our victories which were very hard to get. We value expensive cars, clothes or any other articles. Imagine if your expensive camera would be broken. Will you regret so much if you’ll broke the cheap one?  It seems that expenses by themselves represent value.

Therefore we have another formula:

Value = Benefit + Expenses

How we can distinguish which formula to use. I suppose it will be fair to divide the value concept into product value concept and offer value concept.

Offer's value      = Benefit – Expenses

Product's value  = Benefit + Expenses

If we have 2 offers for the same camera: one is 1000$ and the other is 500$ what offer would be more valuable to us?   

 

If we’ll use the 500$ offer the value of the camera would be decreased because the expenses will be decreased. But the value of the offer would be increased because of the same reason.