I came across this website - http://www.apto.com/. It seems to be Salesforce CRM which already has the org setup in such a way to benefit estate agencies the most.
I wasn't aware that this was possible? I thought the two routes with becoming a Salesforce partner were to either become a consultancy company via the Partner Programme or to upload a managed / unmanaged package to the AppExchange as a ISV Partner.
This seems to be re-selling Salesforce licenses at a markup, justified by a pre-configured org specifying a particular industry?
I wasn't aware that re-selling Salesforce licenses like this was a possibility?
EDIT - some more interesting related information can be found here: Salesforce OEM license restrictions for end users