Specific details about "hdb buyer stamp duty 140 28" is not really publicly available, given that the quantities very likely depict an deal with or internal reference number rather then an ordinary identifier. Customer's Stamp Obligation (BSD) is really a tax levied on all property buys in Singapore, like HDB https://hdb-buyer-stamp-duty-14007418.ziblogs.com/37381003/hdb-buyer-stamp-duty-140-28