The warm weather of spring usually ushers in a flurry of real estate activity, as buyers and sellers begin plotting summer moves. But this year, with different parts of the country on varying degrees of lockdown, and the coronavirus putting the kibosh on many open houses, some sellers may be hesitating to list their homes.

According to the National Association of Realtors, the number of existing-home sales across the country in April was down 17.8 percent from March, and 17.2 percent from a year earlier. And the number of listings, particularly in New York City, was way down as well. For the four weeks that ended May 24, new listings nationally were down 22 percent compared to the same period in 2019.

“Some buyers and sellers decided to take a pause,” said Jessica Lautz, the group’s vice president of demographics and behavioral insights. But “overwhelmingly, our members are expecting that these buyers and sellers will come back into the market.”

For those who were getting ready to list a home for sale, that pause provides a little extra time to ensure properties look their best.

Dr. Lautz and others in the industry recently shared thoughts on which maintenance items and improvements are most likely to provide the greatest return on investment and facilitate a quick sale.

Focus on the Little Things

It’s easy to get carried away thinking about elaborate renovations to kitchens and bathrooms, but there are many small improvements and maintenance items that are equally important. They don’t cost much, but they can help make buyers feel comfortable with a home and reduce the chance of red flags during a home inspection.

Sellers “should sweat the small stuff,” said Kathleen Kuhn, the president and chief executive of HouseMaster, a home inspection company based in Somerville, N.J., with franchises across the United States and Canada.

That includes burned-out light bulbs, which should be replaced. “Otherwise, it’s a question mark,” Ms. Kuhn said, because a fixture that won’t turn on may make a buyer wonder if there’s a problem with the wiring.

Eliminate unnecessary extension cords for similar reasons, Ms. Kuhn said: While you may have added them for convenience, they can raise concerns about the electrical system.

You should also repair any windows and doors that don’t open and close easily, she said, and fix loose or leaky faucets.

If there’s a stain on the ceiling from a toilet overflow, repair the drywall and paint in that area so buyers won’t worry that there’s a leaky pipe. “That stain on the ceiling raises a lot of questions,” Ms. Kuhn said. “We can test and verify that it’s dry, but it will still loom in the buyer’s mind.”

At the end of the day, she noted, a long list of little issues can look like a big problem: “You want your home to come across as well maintained, both in the inspector’s eyes and the buyer’s eyes.”

Watch Out for Home Strain

Hippo Home Care, a home-maintenance service provider that is part of the Palo Alto-based home insurance start-up Hippo, cautions people to watch for “home strain” during lockdown. The company has recently been providing free “telemaintenance” phone calls and videoconferences to guide homeowners through simple repairs, said Andrew Wynn, the director, who has seen a surge in requests.

“We’re spending a lot more time in our houses than we were before,” Mr. Wynn said. “This is really accelerating the use of a lot of appliances and systems, and thus reducing their life span.”

If you don’t want to have to replace such things before selling, he advised, take good care of them now.

Consider the dishwasher. Before the lockdown, it may have been used, at most, once a day. But with so many people eating all their meals at home, some dishwashers are now being used twice a day. If that’s the case in your home, Mr. Wynn said, the filter needs to be cleaned twice as often, to prevent problems.

Heating and cooling systems are also facing increased demand. “As we get into the summer, we’re starting to use our air-conditioners all day rather than just in the evenings and early mornings,” he said, so those filters also need to be changed more often.

And if you have a washing machine that’s being used more than usual and it connects to supply lines with rubber hoses, now might be a good time to upgrade the hoses to stronger, braided stainless steel, Mr. Wynn said, to protect against leaks.

Improve Curb Appeal

When you’re selling a house, curb appeal is important. But at a time when buyers may be looking to limit the number of house tours they take, it is especially crucial.

Mr. Wynn suggested tackling the simple things that many people forget: Clean the gutters, touch up cracked and peeling paint, and trim unruly trees and shrubs.

And if your lawn is patchy and brown, fix it.

“The biggest return on value is generally on yard projects,” Dr. Lautz said, rather than interior renovations. “We have seen that things like just seeding and re-sodding the lawn is very attractive to a potential buyer.”

A 2018 report by the National Association of Realtors and the National Association of Landscape Professionals, for instance, estimated that a $375 standard lawn care service, including fertilization and weed control, could boost a home’s sale price by as much as $1,000.

“People are relying on virtual showings, virtual tours, virtual listings, even virtual open houses,” Dr. Lautz said. “So having something that looks beautiful with photos and videos is even more important right now.”

Enhance the Interior

Indoors, a few key changes — new paint, kitchen updates, bathroom updates, and new or refinished wood floors — can often increase the value of a home, said Rick Rudman, the president and chief executive of Curbio, a company based in Potomac, Md., that undertakes presale renovations across the country.

But be careful with your design choices. “There’s a caveat to all these,” Mr. Rudman said. “They can’t be too personalized.”

The goal is to have “a very simple and clean design, and a neutral color palette,” he said. “Where people start to go wrong is when they start looking at bright or dark paint, or when redoing a bathroom or kitchen, looking at luxury.”

A fresh coat of white paint is a relatively inexpensive improvement that can substantially enhance the look of a home, and one that many homeowners can do on their own.

Refinishing wood floors can be a pain, but if the home is empty, it may be worthwhile. Or maybe not: The 2019 Remodeling Impact Report prepared by the National Association of Realtors and the National Association of the Remodeling Industry estimated the average floor-refinishing job was a financial wash — a $2,600 job could potentially boost the sale price by the same amount.

The value of kitchen and bathroom renovations is far less certain. Sellers might recoup only $20,000 of an average $38,300 kitchen upgrade, the associations estimated, and $20,000 of a $35,000 bathroom renovation.

Of course, some kitchen and bathroom renovations are more appealing than others. Renovations completed by Curbio, Mr. Rudman said, regularly earn more than they cost. That’s because his contractors focus on using simple, inexpensive materials that will appeal to the broadest group of buyers possible, he said — like white subway tile and white Shaker-style cabinets.

“It’s stuff that may not be somebody’s dream kitchen or dream bathroom,” he said. “But what they do say is, ‘Hey, I can live here for three, four or five years, and I don’t have to do anything.’”

Homes with extremely outdated, unappealing kitchens and bathrooms stand to benefit the most from such renovations. So if your kitchen and bathrooms are generally acceptable, focus on cleaning and decluttering instead.

“If you want to get the best price and attract the most buyers,” Mr. Rudman said, “you want it to look fresh, modern and move-in ready.”

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