Hi Ellisoncooper, Welcome to EasyEDA. If you buy your PCBs from EasyEDA (I can't say for other vendors) it costs you the same to have a 2 or a 1 layer PCB. In fact for good manufacturability, 2 layers is preferred over 1 to balance out top and bottom copper distrubution (single sided boards - especially large ones - can end up bending). Unless you have a very good reason for wanting to restrict yourself to 1 layer then it makes life so much simpler to make the best use you can of both top and bottom layers. And that's true irrespective of whethe you are using through hole or SMD components, it's just that through hole parts obviously come with their own vias: with SMD you have to add them if you need to change layers. :) See this post for more notes about making good use of wider traces and copper areas for supply tracks: https://easyeda.com/forum/topic/first_time_PCB_maker_project_advice_-SUO60izRL Whilst there are several good reasons for using 4 or more layers; for most relatively simple (not high speed or RF/Microwave) projects unless you run out of tracking space, you shouldn't need to go to more than 2 layers.