... and the high-performance / conplex aircraft sign-off, RVSM training etc.!
There's a bunch of things to consider, but if your employer is absolutely serious that he wants you and nobody but you, the he'll fork the money over and send you to a TRTO that takes care of both your type rating and the training to obtain your commercial ME land with instrument privileges. This shouldn't take more that 14 days for the LJ-course + another 14 days for the license. Maybe less, but I wouldn't count on it.
And the he will send you to recurrent training at least once a year.
Then we're talking serious and professional bevaviour in business aviation. Best of luck!