Donate buttons and affiliate commission programs

Hi XenForo - two questions if I may:

1. I want to add a donate button to my forum. I also wish to keep my contact information private. I know that PayPal offers this but not an option to retain privacy. I noticed some donate buttons offered on the internet that offer total privacy. Has anyone had some experience with these, and are any recommended?

2. I am definitely doing the donate button. But I was also considering an affiliate commission button as well. I see on the internet that the Amazon and Ebay buttons are popular, as well as Google. However I don't wish to clutter up my forum with numbers of affiliate commission buttons, so i plan on only choosing one. Which one would you recommend, and any reasons why would be greatly appreciated.

Thank you!