FA Acquisition proposal comes to handy while acquiring asset. As you know we have to create asset before acquiring it, While creating asset there is a field where you can give proposed value, and while creating FA acquistion journal you can run the acquisition proposal. The asset and value will be brought to your journal. Same apply for adjustment.
This functionality is provided to meet some of the business scenarios where budgeted amount is entered already and also handy while acqhiring mass assets, you dont need to type any asset