Your only gonna hear Turbocad a hundred times. Anything from 11.2 up works on modern computers but I used a version 10 demo on my current machine. Just make sure it isn't "designer" or any of that home building junk. I have 11.2 deluxe and it does anything I need it to, and it only cost me $11.99 or something on ebay. Theres literal truck loads of left over CAD software on the streets waiting to be sold on ebay, so don't buy the latest thing if you want to save some dough.