How am I getting charged for trading on scottrade?

I've heard that stocks sell in multiples of 100, but I only buy them in much smaller numbers. The price supposedly costs more to buy shares in odd or small numbers, but I'm still just getting charged 7 $ a trade. Also, what investment vehicles can i purchase using scottrade in addition to ETF's, C/D's, and stocks?

There is a spread on "the floor" between buyer and seller. It's easier to unload and buy shares in lots of 100. Breaking up a lot bugs the seller on the floor and those shares will cost a little more. Since NASDAQ is electronic, there is nobody to upset. What you see on the chart is an estimated price. At the exact moment one guy buys a lot of 100 shares of XYZ and one guy gets 75 shares of XYZ. The guy buying 100 shares might get those shares at $35 a share. The guy buying the 75 shares might be buying the exact same shares for $35.25 a share.

I use Scottrade as well, and yes, it is still just 7 bucks, with no minimum shares per trade.

I think you can trade options as well, but you must have some sort of upgraded account, not completely sure about that.

As far as I know I only pay $7 no matter how many stocks I buy.

I have been with Scottrade for a year now. Most stock trades are 7 bucks no matter odd or even #