If you are using a broker, he probably has an "aircraft purchase agreement" of some kind that will establish the purchase price and terms of payment. I think AOPA may have such a form available on line.
I know pro and cons have been discussed before, but I set up a Delaware Corporation for about the same amount as sales tax would have cost me in SC ($300) and then an annual amount of about $150. No property taxes are paid in Delaware (SC property tax on aircraft and vehicles is outrageous) so I save a lot of money. Plus, if you decide to take a partner, you just sell them shares in the corporation without changing aircraft registration and possibly being subject to sales tax again. Something to think about. You can just google "delaware corporations" for more info. A couple of different companies do this.
