Thanks for reaching out! You're absolutely welcome to purchase an iPhone 7 from us (we're pretty much in-laws, lol) you would still need to meet the requirements prior to a successful unlock request. You can check those out here: Unlock your mobile wireless device. The biggest hitch is that you'd be required to be a TMO customer to be eligible, but you could switch until the requirements are met and then switch back once the unlock is complete, if you like? We'd love to keep you in the family.
Manage your T-Mobile account