Hope this helps.
It is assumed that the Seller has to pay transfer taxes on a resale but it could be in negotiation regarding who pays it. If the purchase price is agreed between the buyer and seller, the seller doesn't have to pay the taxes.
It is the same theory when it comes to new constructions. Depending on how both sides feel about the final agreement on the purchase price, the buyer can always ask the seller to pay for transfer taxes and the seller can come back for paying half. There is no law to this issue, it all depends on the negotiation as far as I know.