First of all, avoid "invention promoters" of ALL types. If they want money up front, run away. They all want money up front. If you want to look into marketing help AFTER the patent issues, it might make sense then.
Timing is kind of subjective. When you have something that "works" - even if not perfectly, I think it`s time to speak with your lawyer.
Avoid LegalZoom - they don`t give legal advice and can`t give legal advice. You can not prepare your own patent application properly. That`s not a personal attack - I don`t know you. It is a fact. Don`t do surgery on your pets - it`s just too complicated.
James Lindon, Ph.D. Patent Attorney
Lindon & Lindon, LLC
Patents, Trademarks, Copyrights, Pharmacy Law, Litigation
[this is not legal advice - provided for discussion only]
Intellectual Property for the Individual and Small Business: Identify, Protect, Enforce, Defend.
"Fools rush in where angels fear to tread."