Hello all

Currently trying to produce a database which documents the purchases of a number of real estate tycoons. Basically, 10 business men involved in the purchase and sale of real estate formed a society which meets monthly to discuss potential purchases. Each member holds a portfolio of properties. The database is to show the history of buying/selling of properties amongst members, meeting minutes, etc. I'm having big problems developing a good design however and was wondering if you guys could help me out. Would be hugely appreciated. Draft schema is as follows:

Members {Member_reference, Firstname, Surname, Address, Telephone, Portfolio_reference}
Meetings {Meeting_ID, Date, Location, Minutes}
Current Portfolio Data {Portfolio_reference, Property_ID, Property_value}
Property History {Property_ID, Year, Value at this time, Change in value}
Portfolio History {Member_reference, Property_reference, Purchased or sold, Price on sale, amount to estate agent}
Property {Property ID, Property_property reference, address}

Any thoughts? Sorry if this is confusing. Will try specify more if no one is getting what I'm trying to say!

Thanks a million.