installing a used pop top advise

[surferdave]

Hi All
Looks like I found a used pop top. Going to pick it up in a few weeks. I search the forums and found a few install posts. I did want to ask a few questions additional questions. The pop top is a manual one. Its going on an 03 e350

1. what should I look for when inspecting the used top?
2.Things I should avoid?
3. What advice and or tips and tricks for installing the top that I should know.
3. Any special tools that I might need. I have cut windows in the van before so I have the basic
4. Any parts that will need to be replaced such as seals or anything

Thanks in advance