I am building a form that will send an invoice for purchase of book. The book costs $50 and the user can purchase multiple copies. There are three radio buttons for choosing shipping option, all with a different price. And, there is a a radio button to indicate if they live in the seller's state so that a sales tax can be added (5.3%).

For the shipping, I assume I select price multiplier and radio button one is say "UPS Media Mail:5.50" for a cost of $5.50. But, Form builder puts a Price field below the drop down when I select multiplier. What do I enter?

Similarly, if the user indicates with a radio button that they live in the seller's state, how do I add/calculate the sales tax based on 5.3%?


Thanks

Gary