Buying used - What to test/look out for?

Hi everyone,

following the advice I got on here and other forums I made the decision to spend a bit more than planned and am most probably going to buy a Newton soon. I found an interesting offer online and talked to the seller on the phone for half an hour. He seems really nice and willing to help, I will be able to look at the ready-to-use telescope on the mount, he offered to show me how to align and use it in person.

Everything listed is one year old, barely used and said to be in as-new condition. However, I would like to know what to look out for, what questions to ask and maybe what to test to see if the equipment is really up to par. The stuff I am looking at is

• Skywatcher EQ-6 Pro Synscan GoTo mount

• Skywatcher 250/1200 PDS Explorer scope

• Bresser 2x SA Barlow (2")

• Baader Hyperion 8-24mm Clickstop Zoom Mark III (2")

What should I look out for apart from the obvious? Are there any tests to see if the mount is doing a good tracking job?

Thanks!