Every time I get a set of plans to scratch build I unroll the plans and make a list of stock sizes and hardware needed. I then roll the plans up with the materials list inside and put them away until I am wanting to build it. When ordering balsa I usually order for 2 or 3 different plans at a time to save on shipping and if it is one I know I would want to build again if it is crashed, I order in enough to make an extra kit along with the build. Then I kit the plans and start building. The type of balsa is usually noted on the plan, but if it is not, you need to read up here on RCU for tips for what to use and where it is needed.