Product Information price breakdown in Cart and Checkout support

I have tried multiple ways to customise the product/checkout/ cart to display a clear breakdown of the cost and calculate the below in the cart/order summary.

Standard product purchase price: £

Compulsory transfer fee: £80.00

VAT to be added (if applicable)

Subtotal:

I am using the dawn theme and don’t have access to cart.liquid but I do have access to main-cart-item.liquid

I would appreciate some support

https://regdealers-com.myshopify.com/