Dear Sir, thank you for your kind comments about our fees. You didn't raise your concern about the fees in our telephone conversation. It would help if you had at least mentioned to us your concern so we could try to explain in more detail about the additional charges.
We are happy for you that you have got your tax return completed for only £300.
Please note that our tax return fee for a self-employed individual is £350+VAT, and this is our basic self-employed compliance fee where the client completes the bookkeeping and provides us with the summary information to prepare the tax return. If additional work is involved, as in your case, there will be an additional fee accordingly.
Specific to your case, additional work was involved for your visa compliance purposes. The additional fee was in line with the extra work involved.