and then related to contact, leads, maybe accounts.
Architecture could look like this roughly:
Leads = Requests from your website, phone or similar
Contacts = People, B2C customers, employees of B2B customers
Accounts = B2B customers, notaries, land office, etc. (ideally with the type dropdown to specify which kind of organization you’re looking at)
Property = Custom module with address, sq ft / m², year of completion etc.
Quotation = Could be just that, or built out as a property brochure.