Assignment at a loss

Our client A agreed to purchase a flat off-plan for £450 000 and entered into an agreement for lease.

Unfortunately having been made redundant A was unable to complete the purchase but found a cash purchaser B who is prepared to take an assignment of the agreement for lease for no consideration and will complete the purchase.

However B will pay only £270 000. The original buyer A will have to pay the balance of £180 000 to the developer.

Can readers advise as to who has to pay stamp duty land tax and on what amount? A call to the Stamp Office helpline brought the answer that A would pay on £180 000 and B on £270 000 but I must admit to having little confidence in this.

As a second point does A have a claim to a...