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• Who knew you could convert Leads multiple times? Well if you have Modify Audit Fields permission turned on, you can - the Leads never appear Converted, even though IsConverted=true. Use with caution. With Great Power comes Great Responsibility! https://help.salesforce.com/apex/HTViewSolution?urlname=Leads-are-able-to-be-converted-multiple-times&language=en_US. Maybe for double checking create a validation rule to not Convert if IsConverted=True and the user is not a SystemAdministrator - just in case users need that permission for other reasons (But regular users should NEVER import data, so I don't know why the would have it). 

Sample Layout

After the lead has been set up with the client's fields, it will look something like this. Note the different sections that are clearly identifying what this lead record is about. Some orgs may want the Lead Information up the top. 

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