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I am making a class diagram of a system that will locate, intermediary purchase and scheduling petshops services, the customer will have an option to have a basic or premium subscription (where it will have extra discounts),however I am not able to develop a subscription class, moreover, I need a "billing" class where the profits that the system will have will be accounted for. 
I did not understand exactly what the doubt or question is. What was the difficulty?
– Woss
I don’t think it’s a good idea to use int for CPF, CNPJ and ZIP! Take a look here: https://answall.com/questions/4170/quais-s%C3%A3o-os-tipo-de-dados-apropriada-para-colunas-como-Ndere%C3%A7o-e-mail-tele
– Edjane