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Hello there,We are a developement company and we developed a real estate app for one of our clients that will be selling membership plans. Customers can purchase a plan so they can submit their properties for sale in the directory. The app offers one time off payments and subscriptions.We used paypal for the website and andoird app but for the ios we are forced to use in-app purchases so we plan to integrade it.Questions:Is it true that we can only use in-app purchases? We have submited the app but it got rejected becasue we dont offer apple pay.As a developement company we already have an apple developer membership subscription. Can we use that for our client as well? or do they need to have their own account and pay the yearly membership fee?? Since they are not the developers, why do they need it?Is it true that the apple's fees are 30% per purchase? If not, how much is it? if yes, can someone breifly mention why are the fees so high?Thank you in advance!