BuyInRgltryAdvc
                Mandatory
                AcctOwnr
                Optional
                SfkpgAcct
                Mandatory
                BuyInAttrbts
                Repetition (1..n)
                Ref
                Mandatory
                BuyInStat
                Mandatory
                Buy In Deferral
BuyInDfrrl
                Mandatory
                Definition: Specifies if the buy-in transaction was deferred or not.
Type: BuyInDeferral1Code (String)
Allowed Values:
- DEFY (Buy In Deferred): Buy-in is deferred.
- DEFN (Buy In Not Deferred): Buy-in is not deferred.
FinInstrmId
                Optional
                Qty
                Optional
                BuyInPric
                Optional
                CshCompstnAmt
                Optional
                BuyInSttlmDt
                Optional
                SplmtryData
                Repetition (0..n)