Antonov AN2? Bonkers, but it fits the description! Otherwise a turbo-prop caravan sounds about right.
It may well fit the description but it depends where to fly it.
In the US? No way. The FAA has all but banned them to the airshow circuit. Reason, they don't want $15'000 competition for their industry.
Elsewhere where fuel is cheap, if there is such a place, possibly.
The advantage is, they are cheap. Really cheap. To buy. They are rugged and very reliable. They can be flown single pilot but only certain variants, others need 2 man crew.
Payload, yea, they can carry 1000kg. But they can't carry it for 900 NM. 500 maybe, if you are economical with the fuel. The AN2 carries 1200 liters of AVGAS, good enough for about 4 hours. Yes, we are talking 200 - 300 LPH on that big radial depending on the work. TAS is around 100 kts at 200 lph, you can edge it to 130 but it will cost you. Plus a 100 l Oiltank. The picture of that GA fueller who comes up with one liter bottles is usually quite priceless when you tell him to refill 1000 liters of Avgas and, oh btw, 40 Liters of Oil.
IFR? In Russia maybe, elsewhere, plan a total refit of avionic without any STC!
I've flown the AN2 in pax, paradrop, crop spray and cargo version. A total delight to fly, wonderful handling, will land everywhere and take off again, if you can arrange it to be an airport, take the grass runway. If not, any even stretch of land of more than 600 m around will do. Sometimes less.
For the mission Sam wants it? Probably not.