There is a feedback rating that you may refer to for information on a Pinsiders reputation. Also, when buying any machine it is always better to play it in person, especially since you are new to this. Establish a certain distance that you are willing to travel (say 200 miles) then bring the funds w/ you, Cash on the glass is always the best way. When picking a machine up in person, this will save you on shipping cost, + the aggravation of worry & wait time. You are able to PM (personal message) any Pinsider that has a machine for sale, etc.

Just Google "How to transport a pinball machine" in the search engine & there you will receive all kinds of information. Transporting a pinball machine can seen quite intimidating at first, but it's actually just a process. There are also many answers to your question here on Pinside. Just use the search forum at the very top right.