Still, even there you might be able to rein in costs, by turning the thermostat up or down to save on heating or electricity, learning to garden to grow some of your own food and even foraging if you live in or near a wilderness area.

Cutting costs on fees for subscription accounts, like Netflix or cable, can leave money to eat out—or, conversely, taking a picnic lunch to the park can cut out restaurant expenses while mimicking the experience of dining at a sidewalk café. And rather than ponying up for a round of golf, taking a long walk in the woods can provide the same outdoor experience without the cost.

Public transportation or shank’s mare, instead of a car, can put a big dent in annual expenses, while yard sales and thrift shops can yield surprise finds for wardrobe and hobbies alike. Libraries are cheaper than bookstores, for both books and movies; free classes provide education in areas you may never have considered before; and free concerts can while away a music lover’s time just as easily as those whose tickets gouge holes in one’s wallet.

Still, there’s such a thing as just not being able to make that shoestring stretch far enough. If that turns out to be the case, gig work or even a full-time job, if health permits, are alternatives that shouldn’t be eliminated, much as they may not be at the top of your list.

According to a USA TODAY report, three signs you should watch for on that shoestring that might indicate it’s time to start hunting for work are the rate at which you’re depleting your retirement savings, if you’re going into debt, or if you’ve had a family change that’s impacted your retirement income.

Pulling money out of retirement accounts at 10 percent or more each year is probably a sign you’re going to have too much month left at the end of the money.

Taking more than a “safe” withdrawal rate means you’re eating up the principal that’s supposed to see you through till the end of your life, and that’s a sign that you either have to severely modify your budget or find some way to bring in more income.

Ditto going into debt. If you’re losing money to the interest on student loans, mortgages or credit cards, that’s money you won’t have to live in. When possible, plan on entering retirement with bills paid off so that you’re not spending money to borrow money.

And last but not least, if a divorce or the death of a spouse has terminated or slashed a source of income, or if you suddenly find yourself raising a grandchild or housing a grown son or daughter with no financial input, your whole financial dynamic will change. No shoestring will withstand that kind of stretching, so it’s likely time to find a paying alternative.

It doesn’t mean you can’t re-retire at some point—but you’ll have to take care of those shoestrings so they don’t fray and then snap, lest they trip up all those careful retirement plans you’ve made.

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