I can also help with this, I have been helping a few people already...i can fully modify, anything that LSC is willing to let into their garage. If its just to sell I have found out the the Dominator and Fusilade sell for around $117,000 each and a Baller sells for just over $100,000. If you have space in your garage I will do it a few times. Add me on PSN if you wish and send me a text in game rather than me chasing you. If you can find the car you want and bring it to me that's even better, but I don't mind driving around with anyone until we spot one.
I sniped a parachuter today, just thought I would share It could have been coincidence but when I shot the actually parachute itself it jilted for a second giving be a chance to make a clear shot at them when they weren't moving and killing them