Do I need any tools for AM parts?

I am new to all this resin and PE stuff, and I realize I may need to get some special tools. So, I have two questions regarding AM parts.

1. For right now, I think I'll stick with the pre-painted PE parts, but what will I need to work on them?

2. As for resin, I have heard about washing the parts before painting and also using some sort of primer. Another thing I have heard is that I will need a razor saw. I currently have my eye on three, all of which are from Excel Hobby Tools at Squadron. One is just the handle and a blade that is 1 1/4" deep. Another has the handle and two blades being 1" and 1 1/4". The last one Includes the handle, a blade, and a miter box. So, do I need two blades or will one do just fine? How important is the depth of the blade? Is the miter box really necessary?

Anything else I should know?

Thanks for your help.