There are quite a few agencies out there doing Facebook ads for many businesses. Any of them will be happy to take your money and "give it a try". They have NO idea how to speak with sellers, their needs, their wants. Heck when it comes to real estate, those agencies call real estate agents.
On the other side there are quite a few real estate gurus aren't there? But the ONLY guru that does HIS OWN FACEBOOK advertising in house, is me. Nobody else. Period. Everybody else outsources, and many do so to me. Wouldn't you rather go direct with the source?