The 3.5% is not charged on sales tax, shipping, handling, personalization or other added charges. KitAlly is run by DecoBench, LLC. Read the service agreement or see the FAQ.
Every shop gets every part of KitAlly. Nothing is held back for a dearer tier.
You pay when a store sells, and not in a month when nothing does.
The 3.5% is worked out on the products and decoration before any discount. Sales tax and shipping are left out.
If an order is refunded, the 3.5% already taken stays with KitAlly.
What you charge your own clients is up to you, and you keep all of it.
The credit goes to the shop that sent it. The shop that joins pays the full fee.