Got prospects' names and emails - what to do next?

Hey guys,

I have a prospect list with ~600 names and emails, but I do not know the best way to use it.
Are cold emails acceptable? Do I need to worry about being permanently flagged as spam? Are there better ways to advertise to my prospects?

My project (www.clientcma.com) provides a home valuation service for real estate agents. Home valuation reports are integrated into the CMS and are automatically sent to the agent's clients. Think of it as the bank statement but for your home.