How can I start my subscription at a lesser level, using a credit card and now Apple Pay?

Visit this link for your reference

https://quickbooks.intuit.com/learn-support/en-us/intuit-billing-updates/subscription-payment-options-for-quickbooks-online/00/186408

Make sure to click the Buy button to get the discounted price for up to 6 months. If you purchase from the trial account, you have to pay the regular price. 

https://quickbooks.grsm.io/US

https://quickbooks.grsm.io/us-promo

Hope it helps.