Each type of helicopter is different. But this doesnt mean that it is difficult to buy one that would fit your need for everything would boil down to your priority.
Helicopters are measured in terms of passenger capacity, comfort, versatility, speed, and of course cost.
Choosing the right one for you depends on these criteria. For example, if you want a cost effective helicopter strictly for personal use, you can take the Schweizer 300 or the Robinson R22 (helicopter for 2). It has basic comfort and few features.
The exact opposite are the McDonnell-Douglas 500, Enstrom Shark, and the Agusta 109A. They are fast and more convenient to fly.
In between these 2 extremes are Eurocopter Squirrel and the Bell Jet Ranger. These are single turbine-engined helicopter that are more commonly used for filming work and charter flying. The Eurocopter Squirrel and the Bell Jet Ranger are agile, fast, and comfortable, but are constrained to fly on a fair weather.
This is not the case with the Sikorsky S76 and The Eurocopter Dauphin 2 which can fly at 200mph and can accommodate up to 14 people safely and comfortably.
With these, we can narrow down your...