What is expensive?

What is expensive? Why do you consider something to be expensive or may be even too expensive? (I am not talking about Bugatti, a private jet or a duplex on the 5th Avenue here, just about simple stuff) Do you make a comparison with other alike products? Do you take into account opportunity costs? Do you consider hidden costs? In this short article I would like to talk about the perception of money, or better – understanding for yourself what “expensive” actually means.