letsplayballtickets.com Beware of Extra Charges After the Fact Through This Website, Internet

I recently bought tickets through this ticket intermediary website for a San Antonio Spurs game. Two days later I got two charges from the seller, one for the amount I agreed to pay and a second charge for about $30. I called the website and they said this was for sales tax on the tickets.  They said that they don't know who the seller is or if sales tax will be charged when you place the order. 

They obviously know who the seller is since they must pass the order on to the seller and could get information about sales tax or other charges from the seller when the tickets are listed for sale on the website and disclose the amount of any such charges, but they don't bother to do so.  It was obvious from the woman I talked to at this company that they get complaints about this same issue all the time from unhappy customers but refuse to disclose the amount of such charges upfront.  If you buy tickets through this company, assume that you'll be paying an additional 8% - 10% more than what you think.