Whether you plan to sell your house this year or after your last child leaves the nest, being a homeowner includes keeping the house in tiptop shape.

Yes, you can boost your sale price by updating your kitchens and bathrooms, but buyers will never even see your home’s interior if the exterior scares them off.

Every house needs curb appeal. You want your house to say “welcome” to prospective buyers.

Today’s buyers start their home shopping on their computers or smartphones.

“The first picture they see is the front exterior, so if that’s not good, they won’t go any further,” said David Yocum, a real estate agent with Redfin’s Chicago office.

“If there are no pictures online, the buyer assumes there’s something really wrong with the house and isn’t interested at all,” Yocum added.

Following are some suggestions from experts in the field and homeowners who have upped the curb appeal of their homes.

1. Be objective

“Step back and look at your house as though you’ve never seen it before,” said Chip Wade, host of HGTV’s “Elbow Room.”

“Even if you don’t use it, there should be a clearly defined path to your front door. After dark, the entry should have sufficient lighting. The address numerals should be visible and easy to read,” Wade said. “If your front door needs to be replaced, now’s the time.”

Buyers will notice if your house needs a new roof or siding. These are costly, but they can make or break the sale. Long-term warranties tell the buyers they don’t have to worry about redoing these projects.

One of Wade’s biggest bugaboos is the garage door, which can hog the screen in your house photo. “It’s a necessary evil,” he said. “But a substantial one will look better than a ‘builder-grade’ door. The new wood-look doors look real but are not as heavy as real wood.”

Ideally, your house has a front porch, said Wade. “Short of that, you can add a portico that’s big enough to keep your guests dry when it’s raining.”

2. Enlist the experts

“We did a lot of the work ourselves,” said Chris Berry of the 19th-century house he and his wife, Rebekah, remodeled in Elgin, Ill. “But first, we got professional advice.”

Before they bought paint, they hired a color specialist who helped them choose a palette of colors that could have been used when the house was built.

“And we hired a landscape designer to draft a plan that took summer and winter light into consideration, then planted the plants ourselves to save money,” Berry said.

To define the Berrys’ corner lot, the landscape designer suggested they install an aluminum fence with a wrought-iron look. The fence frames the front-yard view of the house and saves their plants from being trampled by kids who attend the grade school across the street.

If you can’t afford the pros, take advantage of apps and manufacturers’ websites that let you post a photo of your house, then “paint” it different colors or add amenities.

3. Respect the house’s origins

As you undo the remuddling your house may have suffered, “don’t fight the house’s original style,” said John Potter, architect with Morgante Wilson Architects in Evanston, Ill. “A professional designer can help you work with it.”

When Potter designed a remodel of Renee and Garrick Lau’s 1896 Italianate house in Wilmette, Ill., he chose materials his predecessors would have used in the late 1800s.

“We used 3-inch-exposure cedar siding, painted sage, with white trim,” said Potter. “We gave the house a wooden front door, beadboard porch ceiling and wooden front steps.”

Potter kept the home’s original, wavy-glass windows. What they lack in energy efficiency they have in character, he said.

Sometimes the house’s original exterior is there, but hidden.

“Under a layer of aluminum siding was the original siding and architectural details including sunbursts and half-round windows,” said Berry.

The Berrys do their own home-improvement jobs to save money, but he estimates it would cost about $25,000 to repair original clapboards, replace rotted areas, re-create damaged ornamentation and paint the whole exterior of their 2,000-square-foot house.

4. Weigh cost vs. value

Before you embark on home improvements that will enhance your home’s curb appeal, consider how much money you’ll recoup when you sell the place.

Remodeling magazine compiles an annual cost vs. value report. If you replace your unsightly front door with a new fiberglass one, for example, you can recoup 72 percent of your cost, or 101.8 percent if you buy one that’s steel. You’ll get 88.4 percent of your money back at resale if you buy a new garage door.

A new roof costs $19,528 on average, said the report, but you’ll get 71.6 percent ($13,975) of that back at resale. Windows are costly, too, but yield a 72.9 percent payback if they’re vinyl and 78.8 percent if they’re wood.

If you are not selling the house soon, add the value of having that amenity while you live in the house. Many homeowners say they wish they had made upgrades years ago instead of making them before selling.

5. Greenbacks for greenery

There are two components to curb appeal — the house itself and the plants that give the property life. For the lush lawn that buyers want, consider a professional lawn service for fertilizing and weed control.

If you have at least three months until you list your house, the service can seed and aerate it, too.

If you’re listing the house soon, splurge on sod for an instant upgrade. Trim or replace foundation plants that hide the view of your house from the street. Edge the lawn for a tidy look. Post large planters on either side of the front door.