How Much Due Diligence Is Needed When a Company Has a Concentrated Customer Base?

The only ones that I can think of where I invest in companies with a really concentrated customer base It was possible to find information on the customers pretty easily Because they were large well-known companies good credit things like that. There's something that I've turned down for that reason. And most industries where I have a lot of concern about the financial stability of the top customers. We talked about net nets last week when buying a basket of net nets would you screen for quality low leverage?