How do I fix the shipping calculation?

I am currently using Stripe for our credit card processing and I am having some difficulty with calculating the shipping price I'd like to charge.  I would like to have it charge $5 flat rate for 1-2 items purchased (even if it is two different items) or $7.50 if 3 or more items are purchased.  Is there a way to do this?

Unfortunately, in the payment wizard it allows the Shipping cost per product or transaction only. An alternative option that might help is to add the Shipping charges as a separate product to the wizard and use product options with special pricing as shown below:

However, the user needs to select the respective option manually. Please give it a try and let us know if you need any further assistance. We will be happy to help.