Well, I have been around! Both of my parents were British but I grew up in Iran. I then moved to the UK as a teen and finished my studies there and eventually at South Bank University in London. I moved to France 28 years ago and married a Frenchman, so I am bilingual but do not profess to be a translator.
I have worked in the language sector for many years and have taught English at University level so I feel my grammar, spelling and punctuation are excellent. I have often worked in US English and I think I know most of the differences now between that and my own, native, British English.
I will be worth every penny because a) I am Anglophone, in the profession of words, so I will make very few mistakes and therefore save you time (eventually, you will be able to depend on me) and b) I am professional; it is my income after all.