Products

* contains standard price book and we can create multiple custom price books.
* without standard price book, it is not possible to create custom price book.
* Price Book: Same product can have multiple prices based on the different locations. Example take laptops which are cheap in US but INIDA they have more cost like that.
* Which is the child object for the opportunity.
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Lead

* After converting the lead it is not possible to see the lead through user interface.
* While running the reports we can see the converted leads.
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