Please Advice Me!-I want to buy MacBookPro 13" used

I want to buy a notebook MacBookPro 13" used(second hand).
The model that i want to buy is a 13" non-retina(late 2011 ) with i5 2,4 8gb120 SSD.
What are the major objectives that i need to check before i should buy:
Is there any way to verify the autenticyty of the product on-line.
I guess i need to check the Baterry, HDD, the response time, heating time, and so on.
Is there any betchmark to run to chech performances?
MacBookUser please advice me.

Thanks a lot.

 

10x Blueroom. i will try to follow your advices. : )