What you are looking for is a real estate CRM solution. Check out Property Base [0] for a hosted solution.
If you like to invest/waste time and money on a tailor made solution, Wordpress offers a solid platform. If it powers your site it might as well power your CRM, right? You could use plugins like Toolset [1], Pods [2] and more [3] to save lots of time.
[0] https://www.propertybase.com/
[2] https://pods.io/