It is old post and in new version of RealEstateManager has PropertyID auto-increment: feature as you know.
Set Yes if you want to use PropertyID auto-increment. NO if you want use manually entered PropertyID.
Option "NO" will help you avoid the same ID.
To configure ID field so the user would not be able to over write it is customization service. For this need change code of component. It is not easy.
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