The size and capability of the current range of quadcoptors and the multi-rotator drones that are available mean that what they can be used for also varies markedly. Quite apart from the hobby aspects where pilots fly for the sheer fun of it either alone or racing with friends there are some ways you can legally make serious money with your quadcopter. One caveat is that in some countries you will need a license if you plan to make money with your quad. Check with your local authorities first.
There are moves by some large organisations to use drones for the delivery of small packages. Amazon is in trials at the moment. My personal opinion is that this is one of the least useful ways to use a drone and I suspect that eventually the only deliveries will be for small high value items and then there is a risk of theft. However, with the ability of drones to be completely remotely controlled and follow a preset flight path this cannot be completely disregarded.
Because of the agility of a drone the ability to do low-level survey work becomes a very real possibility. They can fly where no other form of aircraft can go and at heights that would breach all the rules of aviation. But their sheer size is a massive advantage when it comes to survey work of all types. With the right equipment installed they can produce 3D point clouds, heat maps, GPR maps, monitor pipelines, monitor open cut and underground mining operations and almost anything else you can think of.
A well balanced quadcopter with a good quality camera on board can produce some of the most amazing photographs you can imagine and some you couldn’t have imagined until you saw them. They can get to places even the hardiest rock climbers struggle with, fly over and photograph swamps and tidal flats they you cannot boat or walk over and peer into animal and bird homes in ways even David Attenborough hasn’t yet managed, although his team are pretty amazing themselves. It is a bit more difficult to photograph wildlife unless you can get hold of one of the very expensive silenced quadcopters as the buzzing noise they make does cause most animals and birds to flee.
One industry which is beginning to use quadcopters is the real estate industry. The ability to fly and film in and around a property is a real money spinner for them. Anything which is able to present the property in a good light aids in making the sale.
Farmers are also using quadcopters, usually with a predetermined flight path, to monitor crops, water levels in dams and troughs, the location and movement of stock etc. This technology saves them huge amounts of time and effort and makes them so much more efficient.
I mentioned pipeline inspection before but there is another type of inspection for which a quadcopter is invaluable. Power lines need inspecting regularly for damage to the conductors, damage to the insulators, damage to the pole or tower, damage to the mounting hardware and vegetation incursion. All of these things have the potential to cause a blackout and they would rather program maintenance than have to go out during a storm to repair broken hardware. Even if the drone is flown by a controller as they walk or drive alongside the power line the fact that they can film everything and get much closer than they could otherwise makes a drone an excellent choice for such inspections.
All of these activities can be contracted out, possibly to you. Do fulfil any such contract you must be able to fly accurately and consistently, have sufficient spare batteries to be able to fly for a whole day and the capability of charging those batteries in the field. Explore the options for RTF FPV equipped quadcopters for you new enterprise.