Proof reader editor type

Simply I wrote a book of about 120,000 words. Although I've proof read it myself about ten times I'm not perfect.

There are things I both miss or cannot spot, years of forum abuse have meant my abilities in writing are limited! Therefore things which look correct to me may well not be.

Thus I see a need for a decent proof reader/editor to have a crack at spotting my mistakes and identifying sentences that only make sense to me and not you.

I'd prefer a fixed amount to be agreed first and the time scales for.

In addition to this you will receive credit when it is republished.

Please note due to the book being written for a British Audience, British English is the only medium I want it to be edited in.