Quick questions on Formation of contract - Eduqas A-Level Law Component 2

Consideration is the element of exchange: each party must give something of value, some benefit to one party or detriment to the other (Currie v Misa). It must be sufficient (real and recognised by law) but need not be adequate (a chocolate wrapper suffices, Chappell v Nestle); past consideration is generally not valid (Re McArdle, subject to Lampleigh v Braithwait); performing a pre-existing duty is usually not fresh consideration (Stilk v Myrick) unless it confers a practical benefit (Williams v Roffey Bros) or goes beyond the duty (Hartley v Ponsonby); and part payment of a debt does not discharge the whole (Pinnel's Case; Foakes v Beer), unless promissory estoppel applies (Central London Property Trust v High Trees House).

The parties must intend their agreement to be legally binding. Two rebuttable presumptions apply: in commercial agreements intention is presumed present (Esso v Commissioners), and in social, domestic and family agreements it is presumed absent (Balfour v Balfour). The presumptions can be rebutted: a separated couple's financial agreement was intended to bind (Merritt v Merritt), and a "binding in honour only" clause can negate intention (Rose and Frank v Crompton).

Explain the postal rule and its limits. [10 marks]

A builder agrees to finish a job for the original price after the customer promises an extra 500 pounds to ensure completion on time, which benefits the customer. Advise on whether the promise to pay extra is supported by consideration. [20 marks]