Relational capital for companies has been theorized and modeled in the past, but so far, no real Web application has tried to bring its value to light, especially concerning the real estate application domain. In this paper, we present the results of our surveys on how the types of relations who have contributed to a product impact price premium and what real estate agencies think about real estate relational value, especially as implemented on our Web marketplace connected to Facebook social network and NEO public blockchain for products certifications transparency.