keep getting message "structurally unable". I have gone through the design with a fine tooth comb and find NO orange highlighted tiles. There are two things that I do notice 1) on the 1st floor, there are two tiles almost in the middle of the plot next to each other that WILL NOT hold a floor tile, no matter what I do, and 2) on the customize tool bar my price is 695,000k but, when go to commit the cost is 697,500k it adds 2500k for some reason(is that normal?).