I believe it is important to state upfront in the OP that the seller is a grey dealer (aka scalper), and the story about being too tall for MS is a bit ... irrelevant. I also wonder why is the OP has site residence in NV and sells the car in TX.
By the way, YOU WILL pay sale tax on purchasing a used Tesla, but you may be able to avoid paying taxes if you sell your car in the same year. Edit: If seller's car is still on temporary tag, the tax has not been paid yet. Expect the price of this car to dive down before pretty soon (perhaps by January 1st).