show subtotal and tax in client pay page

[Blesta Addons]

when a client recieve a email about the invoice due, the pay link page show the invoice's items with the sub-total(tax not included) with the total (tax-included) in the end . the subtotal and the tax amount not shown, so is sometimes confused for the client about the amount, as the items total is not the same as the total shown

item 1 ----- 20$
item 2 ---- 30$
item 3 ---- 10$

Total 72$

the client see a 12$ difference, this 12$ is the 20%Tax . os we prefer to add another rows for sub-total and tax, or show the items price included the tax  like 

item 1 ----- 24$
item 2 ---- 36$
item 3 ---- 12$

Total 72$