Whenever I start on a new project, if it’s anything like past projects, it will be a safe bet that there is no written documentation for the Excel files the client is using. The users will do their best to explain it, then it will be up to me to go under the hood and figure out the nitty-gritty of what’s there.
Here are two things I find useful right from the get-go:
The Eight Things You Should Always Check Whenever You Receive an Excel File
www.mbaexcel.com/excel/the-eight-things-you-should-always-check-whenever-you-receive-an-excel-file
RefTreeAnalyser: The Ultimate Formula Auditing Tool
(an Excel Add-in that is well worth the $35 price tag)
www.jkp-ads.com/reftreeanalyser.asp
Give them a try next time you find yourself taking over an Excel file that was developed by someone else!