5. After section 56E of the Principal Act the following section is inserted:
“56EA. (1) A licensed vehicle dealer may, by writing served on a person, advise the person that, if he or she purchases a specified vehicle at a specified price from the dealer, there is payable to the dealer a specified amount, being an amount not exceeding the amount of tax payable by the dealer on the sale under this Part.
“(2) Where—
(a) a notice in accordance with subsection (1) has been served on a person; and
(b) the relevant sale takes place;
the dealer may recover from the purchaser the amount specified in the notice as being payable by the purchaser.”.