We use an address-based account structure for our Salesforce. This means we only store one account record for any given company, and add their various locations as addresses (or Customer #'s) under the Account.

1. Account: Roche
   1. Address 1: New York
   2. Address 2: Boston
   3. Address 3: California
   4. Customer Number 1: New Jersey
   5. Customer Number 2: London

What our account structure doesn't support

1. Account: Roche New York
2. Account: Roche Boston
3. Account: Roche California

If you see an account already exists but the address you've located does not, add the address to the existing account.