Hi, Sorry if this has been answered before. I have searched the forum but not found exactly what I need to know. I am venturing into the world of Microsoft certification again after a gap of 17 years

. My last MCPs were in NT4 and I had a gap of ten years where I was in Service Mgt but I want to get back into the techy game again.
I am about to get the Windows 8.1 study guides to do the two 8.1 exams but I need to know what minimum amount of kit I need so I can do the stuff hands-on such as automated deployment methods (I assume answer files are still used !!!), virtualisation etc.
I already have two PCs at home but I don't want to muck around with them and would rather have fresh PCs that I can trash, rebuild etc.
How many PCs do I need ? Just the two connected up and have virtual multiple machines etc ? Multiple boot etc ? Would I need Windows Server too ? What other OSs / Software would I need ?
I've been out of the game for a while hence the noddy questions

I appreciate any advice received.
Gary