You were asking for, "literature or information". This website has information as well as Helicopter Association International. However, this kind of data will discuss trends within the industry and is broad scope. You are seeking very specific data for your region. And for that, your company has it.
The have been in business for 15 years and have a fleet of various ships. They have the numbers you need. You need to formulate forward thinking business questions:
Why are we considering buying new helo or sim? To offer a more complete in-house training experience? Advanced training for working professional pilots? Fill a missing or low serviced need? Retiring a high time Robinson? Govt. contract require specific ship and configurations? ( Making money is not an answer, per se, as sometimes you may breakeven or even lose money just to get other work. For example, would an in-house simulator will pull in more new pilots for training. Especially, if it is offered cheaper than anyone else.)
From here you can start asking:
1. Should we sell any existing fleet? Not flying enough, expensive to operate, etc.
2. Should we keep and add more? What type of helo and its purpose. ( tours, training)
3. What is your company good at? How well do they obtain new clients? ie. salesmanship
4. What can they do to expand existing operations? Advertising? Sales reps?
5. Consider your corporate image? Top to bottom, from the receptionist to nice paint on the ships, logos, professionalism, etc.
6. Consider selling the business? Age of owners, may want to retire. Cash out while business is strong and not incur more debt expanding operations.
7. And, with all business plans, the final option is always, "Do nothing". This is a serious and often overlooked option. Sometimes, after you obtain cost estimates, sales projections, etc. you will find that it is best to do nothing and keep on the current routine.
8. Take a hard look are there finances. Are they buried in debt? Do they have the monthly cash flow to consider expensive capital improvements?
This is a not a complete list. It's just to get you thinking beyond the first question of should you buy a helo or a sim. By considering some of these other factors will give you a better understanding of the current business and a long term vision for the company.
Sounds like a fun project. I'd like to see your final report.