Opportunity costs are those costs that are associated with a gain or a loss of revenue or income as a result of the choices you make.
For example: going to college or not going to college
Let's look at not going to college first
You are 18 years old and will be earning $24,000 annually and after 10 years your wages increase by $500/year. After 20 they increase by $1,000. After 30 they increase by $1,500. After 40 they increase by $2,000
28-38 = $245,000 second 10 years
38-48 = $345,000 third 10 years
48-58 = $360,000 fourth 10 years
58-68 = $600,000 fifth 10 years (at 68 you retire)
$1,790,000 Total lifetime earnings (+/-)
Let's Look at going to college
You are 24 years old and your first job earns you $50,000/year because you have a Masters's Degree. After 10 years you receive a $1,000/year increase. After 20 years you receive a $1,500/year increase. After 30 years you receive a $2,000/year increase.
The difference between going to college and not going to college can be offset again by finding different ways to invest one's excess monies whether it be in the Stock Market or in Real Estate. Many people who do not go to college end up receiving trade skills either by investing their own money or by finding employers who will give them the money or train them on the job. Many of these people end up investing in real estate because they can provide the labor themselves.