CRM - Associated Deals by Client - Overview Report

I am looking for a way of visualising in an overview / report, how many deals each client has, we have them detailed by deal type. For example. Client A could have up to 6 deal types. If Client A has all six deal types then there will be no opportunity to sell the additional deal types. At the moment the only way to view this is in the board but we have 5000 clients so a widget/ overview would be much better… any ideas? I