I started my own company overseas which i ran for 20 years until it became obvious that without fixed contract(s), the business model was unsustainable. During those 20 years I was fortunate enough to have a good team and we won some contracts, in the absence of which it would have been impossible to develop the company to where I wanted it to be (in terms of personnel, equipment, facilities and resources). I had an excellent purpose built heliport with all facilities and operated a mix of single/multi helos. I think the general thread perception, or experience is entirely accurate - you better have lots of cash and plenty of patience.
The days of casually starting an operation on the basis of adhoc charters etc are just not realistic. Fixed costs in the business have become increasingly high as regulators mandate staffing/experience levels, facility requirements etc etc. The old ratio of maintenance:flight hours was long replaced by pounds of paperwork:flight hours. I closed the business when it became evident that there was just no more contracts to win on the horizon, and despite having a fairly well established base of business, it just wasn't enough to support even one AS350 with all the attendant overhead. A difficult decision to make, but a good one none the less.
I think smaller operators < 3-5 aircraft are just going to have a tough time of it unless they can identify niche markets or win some type of contract that provides stable cashflow which to a large degree will cover fixed costs.
As sexy as aviation is (and I say that because spreadsheets do make them look good), all I can say is do you home work, detach your emotions and take your time getting into anything before time and the business take a toll on you.
It was an interesting ride though, and one that I don't necessarily regret !