What you get free costs too much.
The gods sell to us all the goods which they give us.
Expenditures rise to meet income.
The gods sell all things at a fair price.
— Proverb
Something you don't want is dear at any price.
— Proverb
A thing is worth what it can do for you, not what you choose to pay for it.
Why so large a cost, having so short a lease, does thou upon your fading mansion spend?
The cost of a thing is the amount of what I will call life which is required to be exchanged for it, immediately or in the long run.