How to buy happiness? Tips on what to look out for

Buy for your interests

What represents a happy experience for one person is not necessarily the same for another. Someone who mostly dines out should probably not use discretionary money to buy a fancy set of kitchen knives. But someone who loves to cook? Maybe so. Rubin reminds us, "Beautiful tools make work a joy."

Buy discipline

Want to improve your diet or fitness but have trouble summoning motivation? Use your money. That might mean choosing a pricier gym that's more convenient or even hiring a personal trainer to add accountability. At the supermarket, it could mean buying healthy foods that are more convenient, like bagged salad. "If you can make it slightly easier to get yourself to do something you want to do, that's a good way to spend your money," Rubin says.

Buy stress relief

Is there a simple fix for recurring arguments or sources of stress, especially with a significant other? If you argue about a messy home, can you afford maid service? Or, can you afford not to get maid service? "The question is always, 'Is it cheaper than marriage counseling?'" Rubin quips.

Buy money peace

"One of the greatest luxuries money can buy is the freedom not to think about money," Rubin says. "Financial security is something that really contributes to people's happiness." Paying off debt is a good idea, and building an emergency fund is an especially good one. It provides cash for not only real emergencies, like a car repair, but all those emergencies in our heads that never happen but keep us up at night because they might. Happiness is silencing the haunting "what-if" voices. "The freedom from worry is a big boost to happiness," she says.

Buy wiggle room

If you have extra cash, use it to allow yourself to be sloppy without consequence. It could be as simple as buying a few extra pairs of underwear so you're not pressed to do laundry every seven days.

Buy a do-gooder high

Be charitable. "Contributing to others is a great way to support the causes you believe in and put your values into the world," Rubin says.

If you add a few of these purchases to your life's shopping cart, chances are you'll be happier when you check out.