may I chime in
in regards to the word " cheap"...
THERE are NO cheap airplanes...
all of the types mentioned above, can be bought on the used market for approximately the same amount of money..
In regards to operating costs, the differences may me very small indeed..
Let us take any airplane from above and let us assume that it is not older than 15 years since build when acquired..
Engines and APU can be "capped" by programs..
how much the airframe maintenance will actually cost over the years depends on the quality of any plane when bought, good history, good pre-buy and good maintenance and operating practices thereafter
All of them will run in the range of between 5K and 6K EUR ( or take the same amount in USD if operating in the US) per hour when flown around 300 - 400 hours a year..
Having said that and taking today's used market I would take the most performing of the above for such missions...not a bird that "just" might make the longest mission on a good day...but one that will do it any day of the year..
and that would mean we are in the F50, F2000, F900, CL601/604 class and aside from the F50 those birds are in fact halfway comfortable for 4 pax on 5 - 6 hour flights..
on any smaller bird you may actually pay the same amount of money at the end, but end up feeling "cramped" in the cabin...and may face days, when some missions cannot be flown non-stop