For a Captain rotational position (1mths/1mths,) you should be looking at around 180-220.000 USD + per diem 100-150 USD/day while on your rotation. Positioning cost covered. Licence, medical etc. covered. Ball park figures. Anything less than that and you shouldn´t be staying for longer than the time it takes to find a better option that values your skills and qualifications - if you´re Captain on a G650 you´ve made it far enough in this line of business to get paid a premium. Good luck.