All good advice you've been given.
I've seen people pay £100 or more to have a cabinet shipped to them, only to find them smashed up, monitor damaged etc...
I'd also reiterate the point about the monitor - unless you know a fair bit about monitor/television repair then a cabinet with a faulty monitor is going to be next-to-useless to you.
The rest of the wiring/joysticks etc is relatively easy to sort out. What is it you're intending to use the cabinet for? Any game in particular? Or just to use as a generic JAMMA cabinet? Or maybe for MAME?
I managed to pick up a Moon Base cocktail cabinet a few months ago, put a new monitor in it, and wired up a SCART socket so that all my consoles would work on it. I've also put an old P3-450 board in it running AdvanceMAME for playing the older MAME games - works really well.