Buying a used laptop?

I'm reasoning of purchase a used laptop...and yes I realize all the faults I can be encountering, only At the moment the price is right... Anyways I want to build a checkout test before I buy the laptop with different software.

I'm thinking something like this:

Check/Software*

Heat/ Speccy (also to confirm components)
Memory/Linux mem testing
GPU/ ? (perhaps a criterion software like Sandra)
CPU/ ? (perhaps a benchmark software like Sandra)
Battery/ ? (I believe there's an open source software to check)
Hard drive/ ? (I'm pretty secure there's an open source software to check)

And of education a digital test to draw from a surface for the unit then a visual test to check for dings/scratches.

So if someone could help me fill out the "?" with specific programs I can use for my used laptop test that would be great.

- Thanks in advance.