Real Estate Agencies used to post property marker signs like this:

Even far off to the side, a bright background color catches your eye:

The signs sported primary colors, reasonably large type, and simple words, making them almost readable in those pictures and definitely legible from the driver’s seat. While not particularly handsome or stylin’, they got the message across: this house is for sale.
Then a strange thing happened.
Berkshire Hathaway somehow got into the real estate business and Borged several of the local agencies. BH being a Name Brand with a connotation of wealth & taste, their branding imposed a subtle touch on the new signage:

No, you can’t quite read that in real life, either, although the agent’s name and number on the header come close to the old standard.
One day, a old-school sign appeared along one of our usual routes:

Although white and green don’t pop out of the background, the sign has enough contrast that you can read what’s needed.
Then they became affiliated with Christie’s, the Big Name in the realm of high-end auctions. I have no idea what Christie’s has to do with real estate, but if Berkshire Hathaway can do it, it seems Christie’s thinks they can do it even better.
In any event, the Christie’s Corporate Standard evidently calls for very, very subtle signage:
That sign might mark a high-end bed and breakfast, but certainly does not tell me that the place is for sale: none of the text approaches readability from the street, certainly not at normal travel speeds, and nothing about it even suggests that I should take action.
A few weeks later, two hang tags added a COMMERCIAL note (the property evidently has potential to become an office or retail space) and the agent’s name and phone number in minuscule type:

After a while, a very bright red do-it-yourself HOUSE FOR SALE placard suggested the property owner wasn’t entirely satisfied with the results to date:

The high-contrast black-on-white FOR SALE header definitely doesn’t match the rest of the sign, but its more legible information might motivate you to pause and puzzle out the rest. The red placard vanished a few days after the header appeared, leaving us with this peculiar mix:

None of the (numerous) Christie’s signs in the area have a header, so this may be a case of a squeaky wheel getting greased. I won’t be surprised to see a corporate image change, including larger type, as these fancy signs weather away.
Perhaps the correct conclusion to be drawn is that, in this Internet age, nobody buys a house based on the quaint custom of driving by a house-with-sign, thinking “Hey, that’s perfect for me!”, and calling the agent, so there’s no need for anything more than a pro-forma marker identifying a property that will be selected by filters applied to MLS / Zillow databases.
The most recent change simplifies the sign to the bare minimum:

Perhaps we’ve witnessed a falling-out over typography?
This began as a test of the Sony HDR-AS30V camera’s resolution, with the obvious conclusion it wasn’t intended as a camera suitable for recording text.
Around here, they print about half a ream of flyers to put in the for sale sign box, and they’re all gone within three days. There are sometimes three cars waiting in line to grab flyers. We’re still very automotive, I guess, or not very internetty.
Paper: how 20th Century! [grin]
That said, we’ll probably do exactly that when we get around to selling this place. Plenty of folks drive by and that’ll let them self-select for motivation.
Some signs have text message IDs and the more progressive agencies display QR codes. For a while, a few houses sported a low-power AM transmitter with a tape loop, although I haven’t seen those lately.