Put ecommerce functionality in a wordpress site

I need to put ecommerce fuctionality into a wordpress site. It's not much. Not like a shopping cart. I'll pay $50-75 for this. I need to make so I can manage it. LIke the amounts used on the pages, streamline the order process like deleting shipping and sales tax. Also making it simple to "Sign up for move events" (which is my version of "continue shopping"), Manage quantities and prices and text on the order forms.