Can I change the look of my PayPal checkout page through MemberMouse?

No. There is nothing on the MemberMouse end that will be done to change the look of your PayPal landing page.  

With that said, there are two things to note:

1. The PayPal account you have can influence the checkout page used on PayPal. As it's a PayPal feature, we are not clear on how this works but we can say that older PayPal accounts will use different pages than new ones.

2. PayPal processes one-time payments differently than subscriptions. One-time purchases will go to a checkout page on PayPal that's significantly different than the one for subscriptions. The reason is that with a subscription, a PayPal account is required; with a one-time purchase, it's not. You can attempt to purchase a one-time purchase product and see the difference.