Q: how do you see your outstanding balance on a financed Macbook Pro?

You can ask Apple via chat >  http://www.apple.com/contact/

Apple Online Store

Apple.com is a convenient place to purchase Apple products and accessories from Apple and other manufacturers. You can buy online, chat, or call (800) MY–APPLE (800–692–7753), 7 days a week from 7:00 a.m. to 10:00 p.m. Central time.

http://osxdaily.com/2013/05/19/check-itunes-app-store-account-balance/

See your iTunes credit balance - Apple Support