Troubleshooter: Take these etiquette tips and pay them forward

This week, we're talking tips. Specifically, who gets them and how much?

We all know - or at least I think we do - that waiters usually get 15 to 20 percent of the bill. But what about the barista, the hair stylist, the cab driver and the hotel maid?

According to Dave Roberts, a professor at UNC's Kenan-Flagler Business School, tips have become more of an expected payment rather than a reflection of good service.

"The sorts of jobs people tip for have a low base salary," he said. "People are dependent on tips."

There are no official studies, but, anecdotally, people are tipping less as the economy has slowed, Roberts said.

Even in hard times, though, tips are a big deal, said Lizzie Post, spokeswoman for the Emily Post Institute in Burlington, Vt., and the etiquette guru's great-great-granddaughter.

"If you have bad service at a restaurant, you're not supposed to take it out of the tip," she said. "If you leave less than 15 percent, the problem never gets solved."

If service is bad, Post said, either alert the manager after the meal, ask to move tables or leave the restaurant.

At a buffet restaurant, Post recommends a 10 percent tip. For takeout service, no tip is necessary.

Hair stylists should get 20 percent, Post said. If the service is performed by the salon owner, ask whether she accepts tips when you make the appointment.

What if you get a $200 dye job? Still 20 percent?

"If you can afford to get it done, you can afford to tip," Post said.

Spa treatments, such as manicures, massages and facials, should get 15 to 20 percent tips, she said.

Cash for coffee?

At the coffee shop, tipping is as murky as a dark roast. Nearly every coffee shop has a tip jar, but Post said tipping is "totally up to you."

If you order a straight-up black coffee, don't worry about tipping and don't feel guilty, Post said. But if you order a double mocha, skinny frappuccino with whip, pop a George in the tip jar.

When you travel, carry plenty of dollar bills, Post said, because you'll need them. The skycap and bell hop get $2 for the first bag and $1 for each additional bag. The concierge gets $5 if he gets you tickets. If he manages to score front row seats to the sold-out U2 concert, tip $10 or more.

Post said you need to leave hotel maids $2 to $5 each day, not just at the end of your stay. That's because a different person may be on staff. And don't hand it to the front desk, because it rarely makes it back to the maids, she said.

And if you have a coupon for a service, you need to tip based on what the full amount would have been.

You'll want to give holiday bonuses to anyone who has made your life easier, such as the nanny (about a week's pay and a small gift from the children), the house cleaner (up to a week's pay and a small gift) and the newspaper carrier ($10 to $30).

Government workers, such as mail carriers, are not allowed to take cash, gift cards or meals, Post said.

"They are allowed to accept snacks and beverages or small gifts, like mugs and hand warmers," she said.

Post recognizes these have been a rough few years with the recession and all. Most of us have taken pay cuts or have had no raise. If this applies to you, it's acceptable to skip the holiday bonus and write notes, thanking someone for their hard work and letting them know you appreciate them.