Would you say this writer is native?
On a quick glance, it doesn't seem to have the usual hallmarks of ESL writing: total misuse of idioms and vocabulary, wrong articles and conjunctions, etc. On the other hand, the writing is really atrocious if the author actually charged money for it and represented himself as a "professional" writer. My guess would be native language speaker who just can't write and didn't even bother to read what he wrote to make sure that the sentences made sense and actually said something. Those are just issues of horrible writing more than of native-language fluency. The writer speaks English well and has a pretty good vocabulary but has absolutely no idea how to write any better than an average 10th grade student and should not be taking anybody's hard-earned money for that garbage.