In my country X means multiply, so in this case multiply by 3 on average.
The McLaren can easily go for 55 tot 70 dollars, the Lamborginni 45 to 55. The Audi is a bit of a problem, low poly jet not game ready, that one seems to have no market target. The Mitsubishi has no wireframes and renders need some update but still could go for 35 otherwise 45 to 55. The helicopter 35 to 45. The Yamaha I would do 90, that model nearly has no competition and if you make stunning renders (also make some close-up detail shots) it could go for 130 or so (that one I would call seriously under priced), on the other two strange cars ;-p pricing is ok.
The thing is you need to know what you want, do you target hobbyist hoe would like to have the models to learn or just own it, or do you target professional users that easily pay 130 with no hesitation.
To give you some perspective I have a forklift model that used to go for 140 dollars and I made total of 2470 dollars profit on it up until now and it still sells from time to time (albeit for less). I made the model in 3 day’s about 4 years ago, back then there was very little competition for the model, now it has to compete against others and license has dropped to editorial and that’s a real killer.
Anyways, lower pricing can make you lose lots of money, professionals do not take your products/profile seriously and there are not that mush hobbyists paying for 3D models.
There are people that would probably not agree with what I say here but that's ok, I’m doing this for a long time and its going fine.
