Running ads and prospecting on social media needs to be a giant part of any agent's marketing plan, but there are a whole lot of situations where email marketing may serve you better.
Having a good line of communication with your prospects or clients depends on their responses. Very few will respond to straight up attempts to land their sale or refer you to their friend.
So you've got some leads that are interested or looking at buying a new house. You need to convert them into clients and the best way is to provide and continuing to provide value to them.