IBISWorld counted 25,247 estate agency businesses in the UK in 2024, and most of them compete over a handful of postcodes rather than the whole country. The site that falls behind first is usually the one still showing property that went under offer in spring. When the feed from the CRM breaks, or was never wired up at all, your website becomes the least accurate place to look at your own stock.
Then there is the valuation itself. Plenty of agency sites carry one contact page with a subject dropdown on it, so an owner ready to put a figure on their house types the same message every other enquiry types. Our experience is that a form built for that single job, asking for the address, the property type and a time to ring, gets completed far more often than a general one.
The third thing is what happens on a phone. Property gets browsed in bed and on a bus, and a gallery that needs two hands, a floor plan that arrives as a download, or a map that grabs the scroll all send the buyer back where they came from. Portals are built around that problem, so your own listing pages have to be at least as easy to swipe through.