Bought used Tein Flex - what can I check before putting them on the car?

[elib]

I bought some used Tein Flex from a member and wanted to see if anyone had some pointers as to what I should inspect before putting the on the car. I know I need to make sure the spring seats aren't frozen but what else? Any way to check the valves or anything else so I don't have to put them on, find out something is wrong, take them off, send them for repair etc.

 

 

Thanks!