I don't think you can find expired domains at discounted prices, quality expired domains (especially niche-relevant ones like you want) that are clean and somewhat decent are hard to come by, so you gotta pay what the sellers ask for. Or, if you can negotiate with them and get a better deal that's between you and the seller, but I've not seen many successful cases of this, so good luck with that
You can find expired domains in many places (NameJet, Dropcatch, Godaddy auctions being 3 of the best ones from what I hear), but I obviously recommend the forum's marketplace as a starting point since there are so many cool things being sold in here. So, have a peep in here first:
https://www.blackhatworld.com/forums/domains-websites-for-sale.195/
Regarding how to rank the site... well, this would be extremely hard to say since we have no idea about your goals, budget, skills, etc.... And the industry (real estate) is ultra competitive too, so this doesn't help either.
So, lacking enough info to make an actionable plan, I will just go the route of giving generic pointers that you can (and should) expand / improve on as you learn more about how SEO works. So...
- focus on local SEO stuff (since I assume you're not a big company with national / multinational reach yet to afford spending $1,000,000 a month on advertising on CNN, NBC, etc ) like having GBP in each location that you operate in, having lots of quality citations (NAPs) in quality local / national directories, gain real and quality google reviews to your GBPs, etc... Unfortunately, I've not done local SEO before, so I can't go into the specifics of how to rank locally, but I've heard a lot of people who do local SEO that GBPs + reviews and quality NAPs are the strong points of ranking locally
- also focus on the low hanging fruit (long tail keywords) since - in the beginning - it will be hard for google to rank you (a random nobody for now) over more established companies, so you gotta approach rankings in this industry smartly, and targeting long tail keywords that nobody else targets + doing local SEO is the smart way of going about this IMO
- also focus on building up the authority of the site as much as you can by building strong and quality links (PBNs and niche edits mostly) with branded anchors to your homepage first, as I doubt that low authority sites rank on page 1 in this touch niche, so you gotta up your authority to get there
- maybe you don't want to hear this, but I will still say it: google are a bitch, and they will tank you at some point no matter how well you play the SEO game. So, try to get traffic in other ways if possible. Try to build up a constant flow of traffic outside of google by participating in specialty forums, travel / real estate - related magazines (both online and offline) and directories, do other forms of advertising / partnerships / outreach to relevant / complementary places (instead of paying $5000 per month on SEO for 1 year until you start ranking, better spend $1000 per month in 5 various real estate related places for 6 months to get traffic and leads, and starting with the 7th month you might be able to have recouped the $30k already invested so you can spend on SEO while still having an established source of traffic already, just in case that SEO might not work initially / at all)... So yeah, try to establish traffic and leads in other ways, and if you manage to do this google might even reward you with rankings out of the blue since you're already becoming popular outside of google and google hates not including popular sites into their SERPs, so it's very possible they'll reward you with rankings regardless of your SEO efforts. But, in order to get there, you need to become popular in other ways (via social media, by advertising on specialty forums / big advertising networks, participating in online and offline partnerships with local radios / directories / magazines / etc)
And that's all I can think of. I know that my tips are not straight to the point, but like I said, local SEO has never been my thing, so I wouldn't know what specifics to give, so either wait for someone else's reply, or maybe consider hiring someone you can trust to guide you and compile a thorough plan to follow as otherwise I don't think you'll get a lot of specialized help for free...
HTH
