I've made three copies of a bat house based up on the Rocket design, posted elsewhere. Example
I started by laying out the pieces on a 4'x8' work surface, assuming I'd use plywood. I ended up with two sheets of plywood to make enough parts for 3 bat houses.
I took the design, along with some plywood, to the Fab Lab at Lorraine county Community College, southwest of Cleveland. They have a Shop Bot and were very helpful in getting me going on that. I cut all the parts and then stalled for a little bit until I joined i3. With the tools and renewed motivation, I varnished both sides of the pieces and put them together.
As it turns out, plywood is not the best choice for this kind of construction. When you shoot screws edgewise to fasten one sheet to another, it tends to splity the layers. Pre-drilling helps, but does not completely solve the problem. If you want to know more, ask!