I would be certain he could do this. Is he trying to sell you this car for sex? If so, I would think that this arangement might not work, at all, even safter the fact. Paper work, DMV, legalities, and maybe he is just a pain in the rear. Go some where else.
Not sure, but, I think the G is for grand touring, very good ride, suspension, good for trips and cruising down the road, nd the LX is for luxury, it should have some high class options; or extras in it.