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HMRC internal manual

Specialist Investigations Operational Guidance

Settlement by agreement: means to fund the offer: offers recommended for acceptance must always be realistic

It is wrong to recommend for acceptance any offer or agreement prepared by a taxpayer or adviser that we feel the taxpayer is unable or unlikely to honour.

There is an obligation in means restricted cases to be satisfied that the taxpayer does stand a realistic prospect (not a certainty) of meeting the terms of the offer.