Hello!

Can you please read the sentence and see if it is OK?

In spite of this, in the opinion of/according to many authors, negotiating process is most often universal and almost always comprises basic phases for which on can, to a great extent, prepare in advance.

I guess in advance is redundant.

Thank you
In spite of this, in the opinion of/according to many authors, the negotiating process is (nearly) universal and almost always comprises basic phases for which one can, to a great extent, prepare in advance.

Universal does not live well with frequency. Prepare in advance is strictly redundant, but it is an acceptable stock phrase.
Thank you Anon. I agree with you on universal.