I do much like what JayS and Citygirl do with one small exception. When I have reached the number of tools needed for building A, I check the requirements for building B and start collecting those. I'm currently about 20,000 EP from gaining the computer store and have had all the required tools for about two days. At that point I checked what was needed for the Pool Hall and started collecting those.

Of course it requires a lot of juggling (and a lot of helping friends, lol) to keep space open in the barn but I've become accustomed to that. Barb