Marketpress product boxes not fixed sizing

I am using global shortcodes in Gridmarket theme to display products from across the network. The product boxes for each item changes in height depending on the length of the item title or if there are extra lines of the item's price (due to a sale price adding an extra line below the thumbnail)
How can I make the height of the box fixed instead of it changing fluidly? It makes the layout of of my products look very unorganized because it is not squared up grid.
Thank you