Agree with your statement that editing job can be assigned only to experienced writers. However, I would also like to suggest that even people with an eye for detail and a good knowledge of language can also be a good choice for an editor's job.
The above statement was to let you know something about me. I have an eye for detail and good knowledge of English though am not an experienced writer. Please find below few mistakes that I found in your project description. Please understand that I am pointing these mistakes only to prove my claim that I have an eye for detail.
Actual text : For minor mistake, you need to fix them with your own.
Corrected : In case of minor mistakes, you need to fix them on your own.
Actual text : *** Before hire you have to go through various types of small tests.
"Before hire" should have been "In order to be hired," Before hire sounds more of a confirmation whereas "In order to be hired" mentions a clause.
Also since you already mentioned "types" in the sentence, the word "small" was not required. It could have either been
In order for you to be hired, you have to go through various small tests or
In order for you to be hired, you have to go through various types of tests.
Again, these are just my suggestions. I am reiterating, I mentioned these mistakes/changes only to prove my statement that I have an eye for detail. I am ready to take your tests and hire me only if you feel I am capable enough to work for you.
Warm Regards,
Ravii