Real estate commissions on homes in the US are typically between 5-6%. And it is usually split between the seller's agent and the buyer's agent (or it goes all to one agent in the case of dual-ended deals). It is also customary for this commission to be paid entirely by the seller (through the proceeds of their sale), though you could argue that buyers end up paying for it indirectly. All of this is generally true in Canada as well.

This is a good set up:

• Sellers don't pay until they sell and have fresh cash

• Money being deducted from proceeds (the "take rate") is a lot less noticeable and has a lot less friction than cash you just have to pay out

• Buyers kind of don't pay

This last point is one of the most important features of how real estate commissions work. Because you have one side of the transaction that feels as if they're mostly not paying, it generally helps to perpetuate the status quo. If both sides had to directly fork out cash, you'd likely have a lot more people saying, "hey, why don't we consummate this transaction over here, on the side, and not pay these fees."

But it turns out that the US Department of Justice isn't happy about some of these policies and practices. More specifically, when the National Association of Realtors does things like this:

• Prohibiting multiple listing services (“MLSs”) from disclosing to prospective buyers the amount of commission that the buyer broker will earn if the buyer purchases a home listed on the MLS (“NAR’s Commission Concealment Rules”);

• Allowing buyer brokers to mislead buyers into thinking that buyer broker services are free (“NAR’s Free-Service Rule”);

• Enabling buyer brokers to filter MLS listings based on the level of buyer broker commissions offered and to exclude homes with lower commissions from consideration by potential home buyers (“NAR’s Commission-Filter Rules and Practices”); and

• Limiting access to lockboxes that provide licensed brokers physical access to a home that is for sale to only those real estate brokers who are members of a NAR-affiliated MLS (“NAR’s Lockbox Policy”).

In fact, these practices were found to be anti-competitive; they were arguably keeping commissions artificially high. So much so that a federal court recently awarded $1.8 billion in damages. It was also decided that no rule or practice should exist that:

• Prohibits, discourages, or recommends against an MLS or MLS Participant publishing or displaying to consumers any MLS database field specifying the compensation offered to other MLS Participants;

• Permits or requires MLS Participants, including buyer brokers, to represent or suggest that their services are free or available to a client at not cost to the client;

• Permits or enables MLS Participants to filter, suppress, hide, or not display or distribute MLS listings based on the level of compensation offered to the buyer broker or the name of the brokerage or agent; or

• Prohibits, discourages or recommends against the eligibility of any licensed real estate agent or broker, from accessing, with seller approval, the lockboxes of those properties listed on an MLS.

Some believe that this ruling -- which will create more competition -- could reduce the $100 billion or so of commissions paid each year (in the US) by as much as 30%. This is possible. I have no idea how this estimate was calculated. But it does make intuitive sense that commissions should come down. This ruling gets at the heart of what sustains the industry: one side of the marketplace needs to feel that they're, mostly, not really, paying.

Over the last few weeks, a number of people have told me that, when it comes to their current home, they have a number in mind. They more or less said, "I've already spoken with my husband/wife about it and, if someone were to offer us $X, we would sell and move immediately."

What's fascinating about this is that it's a form of housing supply that generally doesn't exist anywhere right now. Sure, the people I was speaking with would sell and move for a price, but how does something like this actually happen? How do buyers find them?

I suppose it could happen through word of mouth. I now know their prices and so if someone I know were interested in such homes, I could tell them. It is a low probability, but it's still a possibility. Alternatively, someone (an agent or otherwise) might just show up on their doorstep and make them an offer. My dad actually sold his last home this way.

But again, how likely is this to happen? It doesn't seem scalable. And this is why Zillow used to have something called a "Make Me Move" listing. Rather than a traditional listing, it was a listing for, "I don't necessarily need to sell, but if you offered me $X, I would move." For whatever reason, though, Zillow no longer offers this service. Presumably, it's because it wasn't working. Hmm.

Here's how I'm thinking about it.

Today, most housing markets are binary. A home is either for sale or it's not. Sometimes enterprising people manage to secure an "off-market home", but generally speaking the market is binary. If a home isn't for sale, most people don't usually bother with it. Mostly because they can't easily find it.

But market conventions aside, the conversations I've been having suggest that it's actually more of a gradient. On the one side are people who really don't want to sell. Maybe they're never sellers. Let's pretend that the home has been in their family for generations and so to convince them to sell you'd probably have to offer them an absurdly high price and that might not even do it.

On the other end of this gradient are people who are ready to sell today. In an extreme example, they might even need to sell by a certain date, or else. In this case, a below-market price could get them to sell. They are highly motivated and one sure-fire way to increase speed is to lower price.

But for everyone else in between, it is a big unknown gray area where price and desire to sell are, I would think, inversely correlated. As desire to sell increases, expectations around price probably need to come down until they reach a point where the market can bear it and a transaction will occur. This is my hypothesis at least.

But if it's true, and there's a big untapped gray area, then the housing market is a lot bigger than we think it is.

There's a lot of money at work right now trying to reinvent the way that homes are bought and sold. Perhaps the most popular trend is "instant buying" or algorithmic home buying. I have been writing about this for years, mostly because of Opendoor. But now there are lots of companies competing in this space. With this model, home sellers get the benefit of an almost immediate sale, though usually it's at a slightly lower price.

Redfin, on the other hand, is returning to something that it first tried out back in 2006: a buy now button on its online listings. It failed back then. But maybe it was simply too early. The feature allows unrepresented buyers -- that is, buyers without an agent -- to make online offers. Naturally, it's far from a single click process. But when accepted, the seller ends up paying about half the amount of commission.

According to the New York Times, the company started testing the feature in late March in the Boston area. Of the 120 homes listed on Redfin with a "start an offer" button, 5 ended up being purchased via an online bid. That's more than I would have expected. But Redfin positions these offers as being the stronger option because they save sellers money. There's also an option to tour the home on your own.

Given this initial response, the company is now working to roll out this feature nationally, market by market. Is this the future of home buying?