Golden Rule; Never put in anything in the Ops Man that you can later get pinned for (when you don't abide by it). For example; don't write in that you will do 2 check rides a year if you ever only intend to do 1 (they will nab you for it), etc etc.
If using a consultant, get one who WILL work with you and not against. Remember your paying the money and it is your operation. Proof read everything as if you were a CAA inspector prior to submitting it.
If the consultant won't work this way, go find one who will.
It will work out better in the long run.
Also, think ahead about the types of operations you will be doing (even if not now) because it will porbably cost you every time you want to submit another ammendment!
Happy writing.
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