One of my earliest jobs was working at McDonald's for $4 an hour grilling burgers in front of a hot stove while my manager yelled at me for not being fast enough.

Today, I'm a self-made millionaire. But I've never forgotten how tough service jobs are, and I want to be generous with my resources while building wealth. Lately, though, I've noticed that tipping isn't really a voluntary demonstration of gratitude anymore. It's become a built-in expectation — and an expensive one.

But you can shift your mindset to reward people for great service, while still protecting your finances. While some people may disagree, here are three things I refuse to tip on:

1. At a point of sale reader where no service is rendered

Let's say you go to the mall and buy a pastry displayed at the front counter. The clerk uses a tong to place the pastry in a brown paper bag, punches the cost in the electronic kiosk, and spins it around to you.

You see default tip options of 15%, 20%, 25% or no tip. I'll usually hit that no tip button or adjust the percentage to what I think is more reasonable. 

The same goes for coffee, unless I've developed a personal relationship with the clerk or they lift your spirits every morning.

2. Picking up a takeout order

One of the more awkward tipping situations is when you get to a restaurant before your to-go order is ready. As you're sitting or standing around waiting, you might make some small talk with the person working there.

When the bill finally comes, there's a check with the word "tip" underneath the total. What do you do?

I rarely hesitate to cross a horizontal line across the tipping field. Given that no service was rendered, no tip needs to be paid. I shouldn't have to tip an employee for just smiling and saying "hi."

Now, if I get to the restaurant early and the bartender welcomes me to sit down, pours me a glass of water, and serves me a side of bread and butter, a small tip is in order.

3. Paying a tradesperson for house repairs

When a plumber, electrician, contractor or handyman comes to my house to fix something, even though they are providing a service, I don't tip.

Tradespeople often charge a minimum visitation fee and an hourly rate. Depending on where you live, the hourly fee can be hundreds of dollars. When they provide you the bill, there is no line item for where to tip either. It also can be awkward for both parties to exchange cash in terms of a tip. 

Of course, if my plumber successfully fixes a leak that has bothered me for years, I do leave a generous tip!

My percentage guidelines for tipping

My general rule is that the more I appreciate the service, the more I will tip. I have no problem leaving no tip to someone who provides bad service, is insulting, or treats me poorly.

Here are my general tipping percentages:

• 10%: OK service, but below normal standards (a long wait, forgot an order)
• 15%: Baseline (good service, nothing out of the ordinary)
• 20%: Great service (the service provider and/or establishment also made me feel good for coming)
• 25%: Outstanding service (they went above and beyond, like they customized a special cake for my birthday, fit me in at the last minute, comped a drink or a dish)
• 30%: When a favorite establishment has fallen on hard times or has been vandalized or burglarized 

The best alternatives to tipping

My advice for when you just can't afford to tip or to give as much as expected, is to refer the person or business to others. The more people you tell about it, the better. 

Another way to help a business is to leave a positive review online. The more glowing the review, the more business the person or establishment will receive. It's a great way to show your appreciation without breaking the bank.

Sam Dogen worked in investing banking for 13 years before starting Financial Samurai, a personal finance website. He is also the author of "Buy This, Not That: How to Spend Your Way to Wealth and Financial Freedom" and "How to Engineer Your Layoff: Make a Small Fortune by Saying Goodbye." Follow Sam on Twitter @financialsamura.

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