I'm in the middle of an apartment search. I was reflecting the other day on how much searching for an apartment has changed over the last 10 years. Conclusion: it hasn't changed much at all. It's still necessary to search on a myriad of sites. Most of the time, by the time you inquire, a place is gone. Or the ad was misleading and that "$2000 2BR" is actually "$2000 for the cheapest Studio we have, but we also have 2…
It was hard. There are so many scams out there. If you are not hand curating listings, you have to rely on somewhat novel approaches to filter out all the bad data. For example, any mention of 'Jesus' or 'God' automatically blocked the listing. Sure there might have been legitamate listings, but anytime I would go in and check 99% of the time it was a scam. You also have scams of people listing units they don't own or have any relation too. They ask for a security deposit up front and just pocket it, leaving the new tenant to have an awkward conversation with the real resident.
Data is often unformatted too. Scraping out bedrooms and bathrooms can even be a challenge on websites like craigslist where the listing is just one big paragraph. (Not anymore, craigslist has come a long way, but that's how it was 10 years ago). Often times you had to just search for the closest number around the word "bed" or "bath". Don't even think about getting features like "driveway" or "laundry" out of them.
In the end, we ended up utilizing some pretty intense ETL pipelines to collate historical data, census information, property assessment data, and other things to try to get a more accurate picture on our listings.
But that didn't win out. What won out are the sites like Apartments.com or Zillow, where legitimate property owners can post their listings in a formatted searchable way. We could scrape them and post the same listings on our site, but at that point we were just pushing our customers to another platform that honestly worked better than our own.
We couldn't have the most up to date data, that was determined by how fast we could go back to scrape a listing. And often times we were knee deep in a battle to avoid being blocked by these companies. Often times, after we had exhausted our proxies, the only thing left to use was Tor.