Well, theoretically “no” – all you need is to have an IDX solution from the FlexMLS. On the other hand, FlexMLS told me that field names can vary between different MLSes which will result in some fields not working within my plugin. For example, in AZ we have a field called DwelingType – in other MLSes the same field is call PropertyType… at the same time teh types of the properties are different as well. Currently, I’m working on a solutions where users will be able to re-define field names to match their MLS.