My own experience with patenting is on something I 'invented' many years ago...and is still available
I looked at the whole scenario of patenting and saw too many negatives. Like how easy it was to get round the patent with a small adjustment...believe me it usually is very easy! Just to give you an example, I know of a company who 'pinched' the drawings of an item which was produced to package metal items in plastic . He saw a potentially lucrative market for his own area of expertise and simply changed very slightly the edge configuration from sharp to chamfered and has now a thriving business. He was of course sued by the original owners of the patent but got away with it very easily.
As for marketing, I am a retired Sales and Marketing Manager, so that part is in my genes.
You will do well to find a good company who can guide you rather than act on your behalf. With any project, it is better to be totally in charge yourself so that you don't come across the unexpected.

By the way, my own 'invention' I gave up for lack of funds. It requires loads of money to prepare the moulds.
As for using 'Investment Funds', no fund will provide investment until you have proved it's earning already!!! (Have you seen the so-called investors on'Dragon's Den'?


------------------
Eddie from Rotherham
http://www.music2myears.plus.com