Laura Vanderkam

However, you and these other adult household members would like to start traveling internationally with your kids to see the world before everyone moves out.

Ideally, what it costs to be you in the future will be higher because you're hoping that you, as an entity, includes two international family trips per year.

So you price this out, add on whatever the taxes would be to gross it up, and now you have a different number.

This is what it costs to be ideal future you.

To live the life you'd like, you need to bring in this new number between the two of you.

So you can start looking for ways to make that happen.

Or perhaps one of you would like to take a year off of work.

When you know what it costs to be you, as a family, you can figure out if you can still have that number without one person's income.

Is the other person's income sufficient?

Maybe.

If not, will savings cover it without compromising all other goals?

If so, amazing.

If not, then the family will either have to revise what it costs to be them or figure out ways to replace that income or save it up.

Or maybe the party that wants to take time off work can take a little less time.

But you won't be guessing about what is feasible.

The point is to make these decisions in a more rational way.

Money can be a source of a lot of angst.

But when you know what it costs to be you and what it costs for your family to live in the way you'd like, then you can make mature decisions about how to bring in that amount of money.

The good news is that it may be possible to bring in more money in various ways.

But that is an entirely different subject for a different episode.