A representation that property can be purchased at 'a reduced price', without any mechanism for determining the quantum of the reduction, is too uncertain to found a promissory estoppel. The certainty requirement for promissory estoppel parallels or exceeds that for contract formation. However, a representation that a person may remain in possession of land until it is sold is sufficiently clear and unambiguous to found an estoppel where there is detrimental reliance.
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