Building my computer with recycled parts

I have built my last four computer systems. In each case, I selected the best components that I currently owned used them as the basis for my new system. The new items I bought were usually a new CPU, graphics card, RAM or motherboard, to improve performance. The items I would recycle from my old system would often be the keyboard and mouse, monitor, sound card, and hard drive. Over time, I would then upgrade those items over time. By doing this, I could upgrade my computer in stages and keep the cost low.