The National Association of Realtors last week committed to abandoning a century-old tradition: requiring sellers’ agents to split a service fee, expressed as a percentage of the sales price, with buyers’ agents. Though in theory the rate is negotiable, in practice it has been anything but because of rules the NAR enforces through conditions it places on access to the databases on which nearly all properties for sale are listed. This has led Realtors to agree on a standard commission — that 6 percent or so. This practice limited competition among agents on price and service quality.

The numbers speak for themselves. While commissions in other industries rise and fall with economic tides and technological innovations (think stock transaction costs, sinking from 1.2 percent to below 0.2 percent between the 1970s and 2000), the real estate commission has not. Homeowners selling $400,000 homes, around the national median, spend $24,000 or so in commissions — $12,000 to their agents and $12,000 to buyers’ agents. Add up all sellers across the country, and sellers are paying around $100 billion yearly in commissions, according to a 2019 Brookings report. This summer, when the new rules kick in, that might finally change. Relaxing NAR rules pertaining to commissions, as the settlement will do, could decrease total commissions by as much as 30 percent. Sellers might list their homes for less in the first place. Lower transaction costs could also encourage them to sell more often, bringing badly needed supply to the housing market — and driving down prices even further.

With commissions more negotiable, buyers will also likely have more opportunity to choose agents based on their charges. Want boutique services from the best of the best, always tipping you off to the hottest homes on the market and available to tour them on the spot? You’ll have to pay more for that than for bare bones representation when you’ve decided to make an offer. If you don’t know exactly what you want when you start house-hunting, you might be able to pony up for whatever perks an agent can offer as you go — buying “a la carte,” as some in the industry put it.

This shift should have happened long ago. After all, the internet has made it easier than ever for buyers to buy and sellers to sell without much expert intervention. The only reason it took this long, the public and the courts both began to recognize ahead of this month’s settlement, was NAR-sponsored collusion.

The settlement also has broader lessons for the too-tight housing market: Structural changes to how homes are bought and sold can add up to much more than marginal savings. The scrutiny should continue, including from the White House; President Biden vowed in his State of the Union address to examine title insurance, limiting the money home buyers fork over when they take loans to protect against the possibility that they’ve bought their property from someone who doesn’t own it. These policies usually cost about $2,000 for that $400,000 home. But the president has launched a pilot program that would waive the need for title insurance on refinancing for certain federally backed mortgages by finding methods of vetting titles ahead of time. This should serve as an opening for broader action.

In this same spirit, regulators should make it easier to build — as well as buy and sell — removing unnecessary restrictions on construction. Here, too, Mr. Biden has the right idea: The White House announced last year a plan to reduce “restrictive and costly land use and zoning rules.” Zoning is another seemingly arcane feature of the housing market that disadvantages American home buyers. Unlike real-estate-agent fees and title insurance, though, there is less opportunity to fix zoning, permitting and land-use policies through one big, national policy shift. State and local governments have established reams of burdensome building rules. They will have to undo them to allow the housing supply to catch up with demand. This would take time. But it would be the most important response to unnecessarily high housing prices.