The amount of tips or gratuities should be included when working
out the amount of earnings if there is evidence from the applicant
or employer that they are received. Unless there is evidence to the
contrary, do not assume tips or gratuities are received just
because people have jobs where tips and gratuities are likely to be
received. See
1) Chapter 3 of the Common Subjects DMG if the applicant's
own evidence is being considered
2) Chapter 3 of the Common Subjects DMG if there is any doubt
about what the applicant has said
3) DMG21029 for when further enquiries should be made.