xml file usage

A customer of mine is using a custom made Real Estate management software which extracts the properties' relevant data to an xml file of about 700.000 lines. I will create a website which will give the website visitor the ability to search for the available properties. I am not sure about which is the best way to manage the xml file. Should I use it natively and run the search queries on it? Should I export the data to an MS SQL Server database and run the queries on the database? I have never worked with XML before so I do not have a clue. Of course I would prefer to use the power of coldfusion.

The xml file attached...

Thanks in advance...