Hi, thank you for rewording your question. Before, I understood your question to mean that you were a US taxpayer asking what types of expenses are generally deductible for a high-end auto import export business. Now, I understand your question to be from a Swiss perspective.
When you first purchase your autos from the US, you will purchase them like any other buyer. You will pay the sales tax applicable in the state in which you purchase the vehicle. Some states have lower sales taxes, but the price of the car may be higher, so all things must be considered. I have traveled to another state to purchase a new vehicle for a lower price.
Since you will not be registering the vehicles for US roads, your US taxes should end with the sales tax. If you were going to drive on US roads, you would also be subject to registration and licenses. After purchase, all tax matters should be on the Swiss side of the ocean. Swiss VAT on car imports is currently 8% and customs duties are 4% of the current value of the car.
A link to the US requirements for exporting a vehicle are here.
I'm sure you've seen this many times, but here is a link to the Swiss page you will need to become very familiar with.
I lived and worked in Zurich for PwC and miss Switzerland very much. PwC told us to buy a car locally because the cost to transport and import was too high. But this applied to lower-end cars.
You should not be required to file a US tax return unless you become a US citizen or establish business operations in the US.
I'm sure you've seen this, also:
Thank you for this opportunity to serve you and I wish you success in your endeavors. -Rick