Please take note.
If sell flat first, when come to Alimony, the hb can claim that the $ is used to pay his debts and do not have much $$$ left, ofcoz his personal assets and $ need to declare during the settlement of alimony (forgot the actual term)
If sell flat after divorce, the court order may stipulate certain conditions like, Mr A has to pay 30k from the sale of flat to Miss B for repayment of loan and then split the house 60:40 or whatever ration, thd hdb lawyer might not undertake such the convenvyancing n thus the couple need to engage their own lawyer which is around 1k diff from hdb.
hope this helps