For a platform that enables homeowners to rent directly to industry professionals, with a decent traction on homeowners listing their property: In today's era of advertising/marketing, would you go the route of spending on Internet/social media ads (Facebook, Google, etc), or hire someone for a direct sales approach (door to door) to grow listing/leads?
Feel free to share what other ways you would go about getting home-owners to list their homes..
I think you'd want to make sure to balance the cost per homeowner acquisition with the value each one provides to your platform in the form of commissions to you. Given that, you should spend "more" on reaching homes/homeowners that have a higher intrinsic propensity to become listers rather than "less" per contact for general awareness. I think door to door would be a high cost/low effect model since the hit rate would be extremely low given that most homes aren't likely for rent and if they are, the landlord will not be the one to open the door!
Finally, since you're building a local two sided market, saturation in a geography is important to get the market working.
If it were me, I'd test two 2 things under the umbrella of focusing more tightly on higher propensity potential listers within my target geography.
1) Reach out to people who currently rent out homes
short term and long term (build a list via reviewing Craigslist, AirBnB, VBRO,
etc) This can be offshored relatively easily
after you spend some time figuring out if it is effective. Hit these folks with very targeted messages
about how your platform is better for them than what they are using today. Maybe offer to build each one a custom free
2) Buy/rent a mailing list of small, independent landlords in your target geography (available from 3rd party list providers) and send them a physical direct mail flyer or letter (there are lots of providers that can help with this.)
A well targeted list in both these cases with a finely tuned message will likely be more cost effective and scalable than door to door and more satisfying than social- which in my experience provides lots of "activity" but little tangible results when applied locally to an episodic need such as listing your home for long term rental. Of course, other people will likely have a different opinion.
Best of luck.