Design database for real estate property management?
Properties can be resold multiple times, refinanced multiple times, have multiple loans/cash financing options per, be sublet/subdivided, have to follow government reporting requirements for all of that, etc. You need a thorough understanding of the business and proper specifications; the fact that you asked the question you have asked suggests to me that either you don't, and/or that you lack experience in the biz. Also, "property" is the singular of "properties", so, "propertyID".