I'm pretty good at developing formulae in Excel. Unless it's unusually complicated 1 hour should be enough.
30+ years Experienced Excel/Word user based in Brisbane, Australia, with office and technical background. Good with maths, spreadsheet functions, and macros. Native English speaker fluent in US and UK English.
Recent work on Freelancer;
1. Soccer league table spreadsheet
2. Civil Calculations In Excel
3. Excel Spreadsheet creation for finance company