Of course and have in the past.. With FB's Open graph search you can laser target buyers and weed out tire kickers.. This is a no brainer :)

Absolutely, that doesn't negate the necessity for opt-in and email marketing. Facebook ads extend the funnel. I have worked with real estate Agents this way and found it effective. Please let me know if you need any assistance and would like to arrange an online meeting to review.

Personally I'd stick to optin pages and not listing pages unless you're marketing investment property. But that's "from the hip", the only way to know is to test.

Not really..You would have to create an ad that stands very far out from the crowd...Check out Chris Record on Google...has a ebook called 350 Examples of Dark Post Ads...he does a good job of showing you some real estate ads.. What I have experienced is that you have to spend allot of money to get any ROI...just like real estate in general you have to reach this huge audience..they have to opt-in...and this occurs online with FB ads I would say at 1/10 of 1% of the people you reach. The upside can be if you spend $100's you may get a closing for $1000's... Great and unique offers are the only things that work online so I would put all my energy into creating an irresistible or very unique offer about you or your service...then spend on marketing.

I think it's a great idea, but you need to do good consumer research to figure out your real personas. If you don't, you risk segmenting down too far and not reaching a lot of your audience.

If I were you, I'd do a combo of laser-targeting and also casting your net wider to get them into that email marketing flow you talk about. Then you can see which is more effective and double down on that.

It does get you to a targeted audience, but I wouldn't expect it to work. FB from my experience hasn't proven itself.