Carla,
I would need to better understand the structure of your Projects and how you use the financial fields.
Do you use the financial Fields?
Are there any entries within the Project that would have to be calculated into the final "cost" of the Project (whether adding or subtracting)?
Please provide as much detail as possible for a proper resolution.
If you just need a field on the Property card that allows you to enter the Sold Value, I suggest simply creating a Custom Field and manually enter it. You can then report on this field.