We have a borrower who is purchasing a condo unit in an 8-unit complex. The HOA has a policy for 100% RCV. Would we request them to add us as mortgagee for the individual unit or do we need to have the customer get a separate homeowner's flood policy to show coverage?

If it is a RCBAP at 100% RCV on the flood declaration page - it is fully covered, and you are done. They do not add mortgagees to a RCBAP policy because if there were 100 units, you could have 100 mortgagees. Plus, the policy insures the complex and not individual units.