I believe that most states have sales tax exemptions for merchandise purchased for resale. Check with your state's sales tax department to see if you can obtain a resellers permit to avoid being charged the sales tax by your suppliers.
If you purchase an asset and the sales tax is required, the sales tax should be recorded as part of the cost of the goods or services received. For example, if you were required to pay sales tax on the new company car, the cost of the car will include the sales tax. If you purchased supplies and the cost of the supplies was subject to sales tax, the sales tax is part of the cost of the supplies. If you received services that were subject to the sales tax, the sales tax is a necessary part of the cost of the services.