The unknown private jet looks similar to the Ghawar in The Ballad of Gay Tony, albeit with a different paint job and two jet engines. Unlike most private jets within the series, it does not feature a T-tail. Two liveries can be seen in the original picture: one taxiing in a green livery, and one in blue, parked behind the Shamal.
It is difficult to identify on what aircraft it is based on. The combination of rear mounted twin jet engines on the fuselage and horizontal stabilizer positioning would seem to indicate the Falcon 2000 or Citation Sovereign may have been the design inspiration, although this jet would appear to be larger than both of these. Its wing as seen from the front and the lightly discernible cockpit makes it resemble the Caravelle, or a JetStar.
The final level of Rockstar Games' Max Payne 3 features similar looking jets as background props, distinctively featuring the same body, wings and engine configuration, but bearing a different livery and featuring winglets. The fact that some aesthetic alterations were performed on the model implies it wasn't just a temporary placeholder, but it's still possible to have merely been a scenic prop like in Max Payne 3.