I am in central iowa looking to re-do a 4' by 8' small brick walkway. The home-owner laid it one year ago by himself, and now wants me to re-do it because it has sunken in areas so it looks very uneven. He said he laid down some sand, laid the brick, and filled the cracks with mortar. Any suggestions on how I should go about this to prevent it from sinking. I laid a small patio at the same residence a year ago by using a 3 inch sand base and compacting and filling the cracks with a fine sand and it still looks good. Should I use the same approach for this one or do i need to Provide a cement-base for an area this small?