▁to ▁the ▁bul lock s ▁and ▁£ 2 1 5 ▁to ▁the ▁bar ley ▁that ▁made ▁it ▁a ▁sale . ▁ ▁Indeed , ▁it ▁is ▁not ▁necessary ▁even ▁for ▁the ▁contract ing ▁parties ▁themselves ▁to ▁assign ▁a ▁mon et ary ▁value ▁to ▁the ▁goods ▁for ▁a ▁part ▁exchange ▁deal ▁to ▁be ▁held ▁to ▁be ▁a ▁sale . ▁ ▁In ▁Bull ▁v ▁Parker , ▁the ▁court ▁itself ▁assigned ▁a ▁value ▁( £ 4 ) ▁for ▁new ▁r iding ▁equipment , ▁sold ▁for ▁some ▁old ▁r iding ▁equipment ▁and ▁£ 2 . ▁ ▁If ▁goods / services ▁have ▁obvious ▁mon et ary ▁values , ▁then ▁a ▁part ▁exchange ▁deal ▁can ▁be ▁held ▁to ▁be ▁a ▁sale . ▁ ▁It ▁was ▁held ▁in ▁Ald ridge ▁v ▁Johnson ▁that ▁there ▁were ▁in ▁fact ▁two ▁separate ▁contract s , ▁both ▁of ▁sale , ▁rather ▁than ▁a ▁single ▁contract ▁of ▁bar ter . ▁ ▁And ▁this ▁is ▁one ▁way ▁that ▁part ▁exchange ▁de als ▁are ▁viewed . ▁ ▁Indeed , ▁this ▁is ▁how ▁they ▁are ▁always ▁viewed ▁in ▁the ▁United ▁Kingdom ▁for ▁V . A . T . ▁purposes . ▁ ▁A ▁supply ▁of ▁an ▁old ▁car ▁in ▁part ▁exchange ▁for ▁a ▁new ▁one , ▁at ▁a ▁car ▁deal ership , ▁is ▁two ▁separate ▁sales , ▁and ▁must ▁be ▁recorded ▁by ▁the ▁deal er ▁as ▁such ▁in ▁account ▁books , ▁for ▁V . A . T . ▁purposes . ▁ ▁Techn ically , ▁the ▁customer ▁is ▁making ▁a ▁" supp ly " ▁for ▁the ▁disc ount ▁given , ▁providing