Cost per mille requires only that the publisher make the advertising available on his or her website and display it to the page visitors in order to receive a commission. Pay per click requires one additional step in the conversion process to generate revenue for the publisher: A visitor must not only be made aware of the advertisement but must also click on the advertisement to visit the advertiser's website.
My tip: Have one main credit card. Have a second one that you use for necessities – such as groceries or gas – that offers rewards for those purchases (a lot of cards do) and set the second one on auto-pay. You should be able to pay off a smaller amount on auto-pay if it is a necessity. If you think you cannot, then you may need to cut down a lot on expenses.
Because 2Checkout exclusively sells software and digital products, it is best suited for established influencers whose target audience is interested in buying products in this niche. But while you won’t find any physical products for sale, 2Checkout is probably the market leader in selling software of every type, including very specific use case items (like software that can convert Microsoft Word documents to PDF, for instance).