Connected record path
Expense and mileage workflow
Expense claims are reimbursed from evidence, and mileage is reimbursed from a rate applied to a distance. The two need different records.
Each step keeps its own record. Retain the source document rather than editing it, and review dates, parties, references, and totals before the new document becomes part of your work history.
Log business mileage
Record the date, route, purpose, and distance per journey. A distance without a stated business purpose is the line most often rejected on review.
Itemise the expenses
List each cost with its date, category, and amount, and keep the underlying receipt against the line rather than in a separate pile.
Export before you submit
Keep your own dated copy of what you submitted. Once a claim enters an internal system you usually lose the ability to see what it originally said.