I am in the process of designing a property management application in my language (RTL) similar to Buildium (www.buildium.com/). I got stuck in the Accounting portion of the ERD. I was able to create the Bank Account and Chart of Account (COA) ER. Now I am working on the Bill system. The billing system for items/service done on the property which includes the Date, Due Date, The Vendor, Property, Account (part of COA), Description and Amount.
My question is where to the add the bill and how can I connect it to the Property so this bill only belongs and appears in the that property financials. Additionally, If anyone has an Accounting system ER please share it with me. My ERD is attached.