Hello and welcome to the site. Thank you for your question.You will find most issues are common but there are some issues that are different depending on the nature of work/business.There is general guidance on what is allowable expense in business. HMRC has guidance notes/helpsheets that I find usefulAs a general rule for an expense to be allowable it has to be incurred wholly and exclusively for the performance of the business. This general principle is covered here
Gifts and business entertainment are not allowed as a deduction against profits, see here
Exceptions for small gifts are covered here
I hope this is helpful and answers your question.
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