Whether you kick off retirement with a robust nest egg or just a modest amount of savings, it helps to keep your living costs as manageable as possible during your golden years. Doing so will help ensure that you don't deplete your nest egg prematurely, not to mention take a load of stress off your mind. Here are three expenses that tend to cost seniors a lot of money -- and how to reduce them.

1. Housing

Just as housing was probably your single greatest monthly expense during your working years, so too might you spend a large chunk of money on it in retirement. This holds true even if you own a home whose mortgage is already paid off, since you'll still have property taxes, maintenance, and repairs to contend with.

Older woman with mug in hand looking over man's shoulder as he types on laptop

IMAGE SOURCE: GETTY IMAGES.

That's why it's smart to consider downsizing during retirement. If you no longer have children living at home, and you don't need the space, selling your home and buying a smaller place could save you money on everything from taxes to upkeep to heating and cooling. Plus, you'll have the option to take the proceeds from the sale of your larger home and invest them to generate another retirement income stream.

2. Transportation

It costs an average of $8,849 a year to own a vehicle, according to the American Automobile Association, so if you're a two-car household, unloading one automobile could slash your transportation costs during retirement. And if you only have one car to begin with, see if it's possible to get by without it. If you live in a very walkable city, or one with public buses and trains, you may find that it's considerably cheaper to pay for transportation on an as-needed basis rather than bear the cost of automobile maintenance and insurance.

3. Healthcare

Many people go into retirement expecting healthcare to be fairly cheap under Medicare, only to learn that that's not at all the case. In fact, the average healthy 65-year-old couple retiring this year is projected to spend $387,644 on healthcare in retirement, according to software provider HealthView Services. And if you're doubting that number, consider that it's meant to cover expenses like Medicare premiums, copays, deductibles, supplemental insurance, and services not covered by Medicare, like dental and vision care.

You can, however, lower your healthcare costs by being smart about Medicare. First, run the numbers to see if a Medicare Advantage plan saves you money over original Medicare. Next, choose your drug plan wisely -- find a plan that offers good coverage for the prescriptions you take, and review your options year after year, since plan formulas can change. Finally, read up on the free services provided by Medicare, and aim to capitalize on them. Attending a no-cost well visit once a year, for example, could help you avoid larger bills if your doctor is able to nip a brewing health problem in the bud by catching it early.

Aim to save on the smaller stuff, too

While reducing your housing, transportation, and healthcare costs could help make your retirement savings last longer, there are other areas you can try cutting back on as well. For example, if you're in the habit of dining out frequently, eating out one less time a week and cooking at home instead could save you a nice sum of money over the course of a year. The same holds true for canceling services you don't really use, like the upgraded cable package whose extra channels you rarely watch.

If you're serious about saving money in retirement, go through your budget and see where there's wiggle room to cut back. Doing so could help preserve your nest egg so that it's there for you when you need it.