1) I want to launch the checkout from an email or external link.
2) I would like to be able to send a link to potential members to sign up. For instance in an email or message. Currently I can only link my different memberships to buttons on my site. This means there's an extra step, which means fewer conversions and more confusion.
3) Right now, I have a page with the checkout button on it. Members need to click on that button before they can checkout. Another option is to use the front-end API, but depending on how long it takes for Memberstack to load, this can take a while.
4) Adding the #membershipID to the current page URL should open the checkout.