To generate seller leads you will need 2 basic components:
1) a good landing page and
2) a mechanism to drive traffic there.
I use https://visualfarming.com to capture leads and https://www.realmailers.com to precisely target my farm area with postcards based on home data. I spend $21/mo on the landing page and around $500/mo on mailers. My ROI is easily 3x on this.