Hi Digiprod99
welcome to the Apple (user-to-user) Community.
Re: I am unable to buy a new iPhone 15 Pro Max on installments
Seems for any iPhone 15 model, you may need to pre-order :
iPhone 15 models seem to be available starting Sep 22nd :
Eg: Buy iPhone 15 Pro and iPhone 15 Pro Max - Apple
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Re:
"I am told I need to pay full price with no zero installments as you advertise for the Apple Card on your website!"
We are all Apple users, like yourself. Apple is not here.
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Re: "I am forced to pick a carrier (verizon in my case)"
Seems Products you can buy from Apple with Apple Card Monthly Installments - Apple Support include iPhone.
says:
"If you buy an iPhone using Apple Card Monthly Installments, you'll have one installment due every month for 24 months".
Apple Card - Monthly Installments - Apple webpage
says:
"Apple Card Monthly Installments is an option when you pay with Apple Card
Whether you shop on apple.com, on the Apple Store app, or at an Apple Store, simply choose Apple Card Monthly Installments as your payment option when you make your purchase.
and
"Apple Card Monthly Installments (ACMI) is a 0% APR payment option that is only available if you select it at checkout in the U.S. for eligible Apple products purchased at Apple Store locations, apple.com, the Apple Store app, or by calling 1‑800‑MY‑APPLE, and is subject to credit approval and credit limit."
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Re: I may have to skip my upgrade from iPhone 13 and possibly get rid of my Apple Card.
That is entirely up to you.
All the best :-)