The Property Address is relied on not only to be merged into various locations such as Forms and Correspondence Templates but it also plays an integral part in the Konekta Integration with the third party vendors for searches.
Rather than a data field, the property address must be added as a Contact within your database and then added against the Property_Address participant type on the matter.
With Actionstep a contact must have an 'identity type' of either 'Individual' or 'Company' and because a property address is not an individual you will be defaulted to have the Identity type as a company. Please treat the Identity type of 'company' for any contact that is not an individual.
Contacts that have the 'Identity type' of Company does not mean the contact is a real ABN/ACN company. Identity type selection simply changes the data you capture about the contact ie Individuals require first and last names, but companies just have a single text box.
Here is a short video on how that works
By also adding the property address as a contact it is now opened up the opportunity of being able to search for that Address as you would search a normal client/matter as sometimes you may receive correspondence with just the property address as a reference.