Sorry for the late reply, I was away for the weekend, I saw you had already placed another order so I owe you the extra 7€ you spent for the shipping, let me know if you want a refund
The Flesh of the city LP is £11, plus £1 extra (as you have paid postage on the others too)
both were said by the natives.
Why the first sentence is in simple past and the second is in present perfect? For me both are similar cases. The only difference that can explain present perfect is that the postage is on a new "future order" in the second case, whereas in the first one it is not on a new order. That is the only difference I see.