Barns a very easy to build with the right set of plans. I have built quite a few of them. For simple barns you can usually design them yourself. If you want to get more complex you definitely need at least a rudimentary plan. Remember the more complex you get the more costly it tends to be. If you want to take a look and download a few plans try
. http://www.homeplansforfree.com/index_files/page0013.html.
